hello Ambient,
generally chlorine will evaporate in 24-48 hours (more quickly if you have some air stones in the water) As I understand it, you are right that chloramine doesn't evaporate. However, if you can water houseplants with it, it shouldn't kill you hydro plants. As for the hard water issue, your best bet is to get the test results from your municipality so you can see what is in it. Then adjust your nutrient solution to allow what's already there to be used. Alternatively, you could just mix a standard solution up per instructions and not worry too much about the additional dissolved solids in the water. You'll need to watch out for nutrient precipitation if the water is very hard but otherwise it shouldn't be too much of a problem.

Alright thanks. I actually looked around a bit more and seen that you can use RO filter housings with a garden hose attachment and get no water waste. So I could technically buy 4 RO filter housings, 1 sediment filter, 2 carbon filters, and 1 DI resin filter, then hook it up to a garden hose/faucet adapter.

I'm still looking more into that. Seems the second best option is an in-line filter that can hook up to a garden hose. They also make small rv-filters as well, but don't seem as efficient.

If you look under Sustainable Hydroponic and Photobucket/ChristianWarlock both those problems are solved and water useage decduced drastly. Best thing is you make it yourself.

Regarding reservoir management, it isn't necessary to completely change your nutrient solution during the course of your crop's lifecycle (let alone every two weeks). If you have a pH/tds meter you can easily manage your solution; without a meter, it is possible to rely on a heuristic (i.e. rule of thumb) such as alternating the addition of pure water and adding 1/2 strength nutrients to the reservoir; the water will be consumed by the plant at a faster rate than the nutrients, thus your tds/ec will begin to rise - that is why I recommend a lower dosage than recommended by manufacturers. Regarding pH, water will raise your pH while nutrients will lower the pH - the trick is keeping it balanced within the appropriate range for the plants you are growing.

Regarding water quality - I can't overstate how invaluable my reverse osmosis unit is to my growing.

How about collecting and using rainwater, would this help? I am new to this hydroponics adventure, (at the moment I am in the “research stage”) and having lots of fun reading about it. Very soon I’ll be asking many questions.

I built my own water filtration system using a series of water filter housings and replaceable filters. using housings like this Filtration Housing. I'm currently using 4 filters (1 seatmate, 2 carbon, and 1 absolute one micron filter). It's completely adjustable. Simply by adding another filter, and/or just changing the replaceable filter cartridges to another type of filter.

As for using rain water, it's completely up to you. Just keep in mind that rain water is not "pure" water, even though it wont have the mineral content that most tap water does. Rain falls from the sky. It passes through the atmosphere on the way down from the clouds. Now assuming you don't live in a city where acid rain could be an issue, the rain still will collect airborne pathogens and fungi spores as it falls through the air.

But the main issue is how you collect and store the rain water. Are you collecting it from your roof and rain gutters? If so your roof isn't clean and neither is the rain gutters. Their both full of decomposing organic mater like dead leaves, bugs, rodents, bird and other animal poop etc. etc.. All of which is a breading ground for pathogens, bacteria, as well as fungi to thrive. I would never use for hydroponics (or any household use) it without filtering it first. I would also use UV treatment in or before the storage tank as well.

Thanks all for the feedback(s).

[8planets]
Yeah I was under the impression that changes like that(2 weeks) were not as necessary as people made them out to be as long as upkeep(TDS/ec/ph/water) was in check.

Replacing @ the end of a crops lifecycle would be confusing to me. Since there will be certain plants that are weeks ahead of others, but I guess it's based on the seniority plants(that have been in there longer).

Do you do changes(cleaning your system) or do you just monitor everything and fill(water)/adjust(ph/tds) as needed?
At what point do you change everything out and clean the tank etc(assuming you grow hydroponically)?
I can't really pinpoint any negatives for not replacing water(nute solution) every 2/3/4/5+ weeks. So I guess that I will just do upkeep. I will have sprayers though(NFT aeroponics) so I will have to check into what is able to be built up into the sprayers(ie: some people say minerals can get stuck in the sprayers overtime and that flushing the system with a solution can help clean them out/probably just a gimmick to buy more crap though).

Do you use a full RO system(w/ membrane) or just filters? I would like to add the addition of a membrane(since it seems to get out metals and such), but it seems that every membrane needs a dump/drain tube(I'm just assuming since a lot of them are setup that way). Not sure if having a flow restrictor placed before the membrane would alleviate the need for water to be dumped(easing pressure on the membrane). I might just stick with filters w/o a membrane. Unless I were to add a perm pump and dual membranes, which would be costly(100-150$ extra).

[CMD1953]
I don't plan on using any rain. I was thinking about doing this as an alternative water source, but came to the conclusion that the stuff in the air would negate the whole purpose(like homehydro said, for city people that is). Plus I live in an apartment and it's not that feasible to catch rain.

They have rain gutter filters, that you can place in the gutters, but I think they suck & have terrible reviews.

I would probably just gather up some 1/2 - 3/4" PVC with 90s, tees, straight pieces and make a hexagon or suitable polygon type shape out of PVC. Buy some zipties and place tarp(most if not all are bpa free) over it. With maybe a funnel of some sort @ the bottom and have the whole setup connected to a reservoir/trashcan(can have multiple funnels & trashcans/reservoirs). Then all you need to do is find some way to place filters(gutter guard/screen door stuff/etc) in that funnel. You have to support the structure as well. Maybe bricks for the water tanks(reservoirs/trashcan) and have the PVC connect to the base or bricks/etc. Could be good for plants, not sure about drinking since it would be hard to filter like that, but the above is just an idea.

[Homehydro]
That's what I plan to do, seems like the best way.
1st Stage: 5 Micron Sediment Filter
2nd Stage: 5 Micron Granular Acivated Carbon(GAC)
3rd Stage: 5 Micron Carbon Block(CTO) Filter
4th Stage: Refillable DI Resin Cartridge (seems 3 lbs of resin will last 2 1/2 - 3 years)

(already got the product list and everything is ready to go)
4 1/4" 10" clear housings
2x dual housing brackets
2x 1/4" garden hose adapters
2x 1/4" push connect fittings
3x 1/4" nipples
Around 10 foot of 1/4" tubing(black) (won't need 10', but more is better and it's cheap stuff; .25cents for 1')
25' 3/4" soaker hose from harborfreight
(all mounted under a faucet area or on a 2x4 to make it portable)

Just trying to figure out if I should add a 5th stage for another carbon or GAC filter for better chlorine or chloramine(GAC) filtration. I have chloramine which I think the GAC filter takes care of(not sure how good it does).

As I mentioned I am new to hydroponics and the information about the rainwater was something that I read somewhere. Thanks for bringing it to my attention I will definitely remember when I get involved with building and using a hydroponic system. Also I read somewhere about using distilled water is that any better?

Hopefully someone can get back to on you on that question of distillation because I have no clue. Would seem that you would need to test your water first, then figure out what distillation would decrease on what PPM your water is at. If you have chloramine, then you more than likely might need better filtration.

Do you already have a distiller? Would seem like a hassle to get a large amount of water out of it and it would seem costly to purchase it as well(depending on how many gallons you may be needing). Not sure how fast they work, just thinking out loud.

That's why people use water filters rather than distiller. A distiller is fairly easy to build, but not worth the cost to make water. But moonshine on the other hand, that would be worth it.

Also, only partially changing your nutrient solution is what a lot of people do. However there is a balance that needs to be met. That's a balance between a well balanced nutrient solution, and acceptable plant health problems. There isn't a PPM/TDS/EC meter made yet that can tell you what nutrients are in the water, and most importantly in what concentrations each are in. The readings only give a total of everything in the water. They don't, and cant break it down. That's their limitation.

If you only partially change the nutrient solution, that only slows down the inevitable. That's an unbalanced nutrient solution. In other words an unbalanced concentration of each individual mineral element. Plants don't take up the mineral elements evenly, they use what they need and leave the rest. so the ones they use often can be replaced, but the ones they don't use will wind up in toxic concentrations. Commercial operations use lab testing, as well as strict monitoring to evaluate the concentrations of each mineral element. They don't rely on EC/TDS/PPM readings by themselves.

It only cost me about 2 cents per gallon of nutrient solution. So it's much more cost effective to change the nutrient solution regularly, than pay to have the lab testing done, much less even buy a EC/TDS/or PPM meter. Even if I were to buy a meter, they are electronic devices that can (and will) give false readings. It can be a useful tool in the right situations. But understanding how they work, their limitations, as well as how plants take up nutrients is key to them being useful.

If I were given a bag of nutrients in one hand, and a EC/TDS/PPM meter in the other hand. Then asked witch do I want to take home. Keep the meter, I cant eat electronic devices. I can grow plants with nutrients.

Ah ha. Forgot to factor that in. Would seem like common sense, but I didn't posses it. Thanks for clarifying on that topic.

I will just stick to a 2 week period(less during their starting phase), make sure water is at optimal levels/pH in check, then replace the nutrient solution. Guess that's a good schedule, was just basing it off what I was told from someone @ general hydroponics(was going to use maxigro). Will just have to see how fast 36 plants use a 27(a few less) reservoir.

Thanks for the feedback.

OP/Ambient,

I am relatively new to hydroponics(been at it since February now). I was faced with more or less the same dilemma that you have. I tried using tap water only to find that I experienced nutrient fallout in my reservoir.

I've looked into RO systems, but with the many other expenses related to my greenhouse hydroponics, I have decided to simply purchase RO water for the time being. Perhaps next year I'll buy this:
http://www.bghydro.com/BGH/itemMatrix.asp?GroupCode=WTROSTL00&eq=&MatrixType=1

In the meantime, the best advice I was given is to purchase R.O. water from an aquarium store. The local one to me sold it for $.50/gallon. I also found a local stand called arctic water on a streetcorner that sells RO water for $.25/gallon or $1/5ga.

With prices that cheap, it makes the decision more difficult to buy an RO filter out the gate. ;)

After everything is said and done. I will be out around $120-150 for a 4 filter system, the one I listed above. Not accounting for replacing the filters every year, but that is around $30-40 depending on it's replacement rating.

I guess it just depends how big your res is and how often you change the solution. I would have two 27 gal reservoirs + a 7"x4'x4 lettuce raft.

Say I'm just using 50 gallons, not even factoring the raft.
That's around 300-325$ a year(240-260$ for $1/5gal) not factoring in any gas/tax or back/shoulder repairs needed from carrying all that to and from your vehicle :) .

Keep in mind that RO systems waist at least 3 times more water than you get. If you use 50 gallons, at least 150 gallons went down the drain. And water from the pay machines isn't always the greatest. It depends on how reliable they are at replacing the filters when needed.

I neglected to mention in my previous post that I used my TDS pen and came up with 16ppm from the aqaurium store, and 8ppm from the corner-side stand. I've been able to find two of these corner-side stands now in my area, and both have water quality roughly about 8ppm.. which is nearly as good as distilled water. :)

But homehydro does have a point that it is totally dependent on upkeep of the filtration system. I'd always measure the water quality before deciding to purchase in quantity.

Ambient - when I first started, I used to haul water (either distilled from the grocery store or RO from aquarium/pet stores) and suffered the monetary and back pains - either way, I found it to be inefficient. I'll say it again: the two things that really helped me out when making the transition from beginner to larger-scale hobbyist were (a) a reverse osmosis system and (b) a combination meter. You can get a relatively-cheap unit like the Hydro-logic 100 and not need to change the filters for quite awhile (e.g. over a year). I now do hydroponics for a living - one aspect of my business is the growing and selling of gourmet crops to local restaurants and farmer's markets.

Regarding the comments by homehydro, it is true that current combo meter technology doesn't break down the individual nutrient levels from the aggregate ec/tds readings. (Sensors are being developed right now that can effectively monitor individual levels - it's only a matter of time until they will also be commercially available.) But it is ridiculous to claim that nutrient toxicities are inevitable in a recirculating solution without changeouts.

Without a doubt it would not be feasible to have a hydro growing career and do nutrient changeouts every two weeks; currently, two of my reservoirs haven't been changed for six months - yet none of my plants have developed problems. Rest assured, I am not alone in this approach. NASA has conducted a myriad of experiments using solutions for multiple years without testing the solution composition because that would not be feasible in space (e.g. International Space Station can't send samples to Earth); it turns out, toxicities are NOT inevitable if you use a bit of common sense: run your nutes at a lower strength, alternate topping-off the solution with dilute nutes and water, etc.

Think about this: hydroponics is always touted for being efficient compared to soil-based growing in terms of nutrient use and water use; these claims aren't compatible with the notion that complete changeouts need to be done on a normal basis. Every two weeks - give me a break (you sound like you work for a nutrient company).

And one final thing: homehydro said "If I were given a bag of nutrients in one hand...blah, blah...I cant eat electronic devices. I can grow plants with nutrients." This statement is so ridiculous, it's not even wrong...it's just ridiculous...

Returning from my rant, Ambient I'm sure you will do what is best for you, but I wanted to just reiterate my two cents worth of advice: RO system is totally worth saving the cost in dollars, time, and back aches; and use common sense when it comes to nutrient management and your plants will be great.

I think nutrient change-out is more based on reservoir size. A larger reservoir has more of a buffer against out of whack nutes. I would be much more likely to change out a small 5 gallon res every two weeks (not just because of the money).

Also, a lot of people I talk to change out when they top off with the amount of water equal to their reservoir size. So a 30 gal res is changed when 30 gal of water/nutes has been topped off.

I have a 30 gallon res, and I only do a change out when fruiting has begun.

I have hardwater myself, 300ppm 7.8 pH. I've been using General Hydroponics Hardwater with no problems. There is nooooo way I would go out and buy water, thats just silly.

8Planets,
Sensors are being developed right now that can effectively monitor individual levels - it's only a matter of time until they will also be commercially available
Great, when a reliable version becomes available to the general public at a reasonable cost, let me know. I would love to have one.

But it is ridiculous to claim that nutrient toxicities are inevitable in a recirculating solution without changeouts
So you believe that the plants use all the individual mineral salts in exact equal amounts do you? How do you come to that conclusion?

Without a doubt it would not be feasible to have a hydro growing career and do nutrient changeouts every two weeks
What are you referring to as a career? A backyard grower, or a commercial enterprise? There's a huge difference in how a commercial enterprise monitors their nutrient solutions and plants. Though for the backyard grower, those methods are basically out of the question due to costs (unless you have money to waist). Those methods include regular lab testing of mineral content in the plant tissue. That tells them what the nutrient solution is lacking, or in excess. Commercial operations also custom make their nutrients, and can add only the specific nutrients the plants take up quicker. The regular lab testing tells them when and what to add to make sure their nutrients are balanced, not a PPM/TDS/EC meter. If you are actually concerned with water usage, how do you justify wasting 3 gallons of water for every one gallon you get from your RO system?

currently, two of my reservoirs haven't been changed for six months - yet none of my plants have developed problems
First there are a whole lot of variables that are not mentioned. Second, have the plant tissue lab tested for mineral content (like commercial operations do regularly). Sure NASA dosen't send samples to earth, that would be a waist of rocket fuel, they have all the testing equipment and materials they need already on the space station. I'm glad you have the same type of funding that NASA has. Want to share some of it with us poor folk?

it turns out, toxicities are NOT inevitable if you use a bit of common sense: run your nutes at a lower strength, alternate topping-off the solution with dilute nutes and water, etc.
No, that wont make it not happen, but it does slow down the proses quite a bit. Also the size of the reservoir in comparison with the amount of plants, as well as the size of the plants will make a big difference. Not to mention other environmental aspects like temp and humidity that have a huge affect on how much water and nutrients the plants actually take up to consider.

Think about this: hydroponics is always touted for being efficient compared to soil-based growing in terms of nutrient use and water use; these claims aren't compatible with the notion that complete changeouts need to be done on a normal basis. Every two weeks - give me a break (you sound like you work for a nutrient company).
Consider yourself on break. The notion that hydroponics uses less water and nutrients is completely valid. If you had the same plants in the ground, how much water would you be dumping on them every two weeks? At least 5 times more than any hydroponic system used in that same amount of time (unless it rains a lot where you live). In terms of nutrients, the nutrients are recycled through the system. In soil there are two problems. First is that very little of the soil nutrients are actually water soluble, and the plants cant use them at all if their not water soluble. Where hydroponic nutrients are 100% water soluble. The second problem with soil nutrients is that most of the nutrients that do dissolve in water, never actually reach the plants roots where they can be used by the plant. They just wind up draining down into the water table below. In hydroponic systems the nutrients are brought to the roots, and continually recirculate where they can be used by the plant.

And one final thing: homehydro said "If I were given a bag of nutrients in one hand...blah, blah...I cant eat electronic devices. I can grow plants with nutrients." This statement is so ridiculous, it's not even wrong...it's just ridiculous...
Really? In what context? Actually the nutrients are almost cheaper than the water. At least the type I use are, so I have no issue changing them out. The nutrients only cost me about 2 cents per gallon of nutrient solution. A 20 gallon reservoir only cost me about 40 cents in nutrients. If I changed it twice a month, that reservoir would only cost me 80 cents a month in nutrients. Times 12, that comes out to less than $10 a year. That's 26 complete nutrient changes. I could change 200 gallons of nutrient solution every 2 weeks for an entire year (26 times) for the same $100 that EC/TDS/PPM meter cost. Where I come from that will grow a whole lot of plants. In what context is that ridiculous?

P.S.
For the record I don't have any specific time period that I always change the nutrient solution at. There are so many variables, and each system, crop, weather conditions etc are different. I use my experience to judge when to change them. I sometimes change them once a week, but have often let it go 4 weeks before changing them. One to two weeks is just a general guideline I use for new growers. Over time they will gain their own experience, thus be able to judge when to change theirs in the same way.

Actually, it's not THAT expensive to test your nutrient solution for individual minerals. there is a cost but it is not astronomical. More than mosts hobbyists want to pay, but basically negligible for a commercial operation. you basically test the nutrient solution itself to determine how much of each mineral remains. Then you add back what is needed to balance the nutrients. kits that measure all the major minerals are, I believe, about $400 for maybe 50 tests. While that's no small bit of change a happy compromise could be found. basically you keep a steady EC level for about 3 months then balance you nutrients after that. so you're looking at using 4 of the tests a year. so you testing materials will last about 12.5 years on one reservoir.
Or you could dump your nutes every two weeks and hope it doesn't find its way to the water table.

Okay homehydro, let me correct some of your more egregious assumptions and generalizations.

First, you said: "So you believe that the plants use all the individual mineral salts in exact equal amounts do you? How do you come to that conclusion?"

No, didn't say that...in fact, I think that is also ridiculous. How did you even jump to that conclusion. You see, the reason I don't develop toxicities is because I have a thorough knowledge of the proportions of the essential elements and their plant uptake rate based on stage of growth. So, I know how to efficiently manage nutrient solutions.

Second, you said: "Commercial operations also custom make their nutrients, and can add only the specific nutrients the plants take up quicker. The regular lab testing tells them when and what to add to make sure their nutrients are balanced, not a PPM/TDS/EC meter. If you are actually concerned with water usage, how do you justify wasting 3 gallons of water for every one gallon you get from your RO system?"

No, that's just ridiculous. How can you generalize about the procedures of all commercial enterprises. You see, I used to work on hydroponics for a large, commercial aquaponics venture in NY. Guess what we used to manage our nutrient solutions? That's right: knowledge of mathematics, plant biology, and wait for it: combo meters. We even used commercial nutrients (not custom) to adjust the nutrient solutions. And yes, we were quite successful - only on rare occasions when an undefined problem arose did we turn to lab testing: I'd say once every year, if that. Oh, and on the issue of wasting water, perhaps you could think of other uses of the discharge water from a RO system - it doesn't need to simply drain away into the ground...hmmm...

Third, you said: "Sure NASA dosen't send samples to earth, that would be a waist of rocket fuel, they have all the testing equipment and materials they need already on the space station. I'm glad you have the same type of funding that NASA has. Want to share some of it with us poor folk?"

Hahahaha! Really, NASA has a lab on the ISS? Excellent, did you just make that up, or do you know someone at NASA who is pulling your leg? And do I have the same kind of funding as NASA? No, not exactly - in fact, not at all. I quit my previous jobs as a college instructor and the aquaponics venture to branch out on my own, so my "funding" is what I make. You see, the fact that I started my own business is what pushes me to be as efficient as possible.

Fourth, you said [regarding toxicities building up]: "No, that wont make it not happen, but it does slow down the proses quite a bit."

The European Union has been forcing tougher environmental standards on hydroponic growers to limit their reservoir discharges because drain to waste, and full changeouts, are huge pollutants. Are they all going to fold because of toxicities? Nevermind that I don't discharge my reservoirs - completely or partially - unless I develop a severe problem, which is exceedingly rare. I'm growing several batches of hundreds of plants on those two reservoirs that haven't been changed over six months, and you're telling me I'm doing it wrong? Wow...

Fifth, you said: "The second problem with soil nutrients is that most of the nutrients that do dissolve in water, never actually reach the plants roots where they can be used by the plant. They just wind up draining down into the water table below."

To reach the water table, they must travel past the plants' roots - simple logic. And yes, I do get enough rainfall that I don't have to irrigate my land regularly - I don't live in a desert; but if I did, I sure as heck wouldn't discharge my reservoir on a regular basis; I would learn how to be efficient with my nutrient management practices.

Finally, you said: "If I were given a bag of nutrients in one hand...blah, blah...I cant eat electronic devices. I can grow plants with nutrients."

This is mainly your most ridiculous point because it is a false statement. Sure, you can't eat electronic devices, but you also can't eat plant nutrients. Likewise, you can use plant nutrients to grow plants, just like you can use electronic devices to grow plants better.

One last thought: hydroponic science is presently going through a rebirth, spurred by rising food costs and need for greater efficiency. In the future, heuristics such as full changeouts once top-off volume = res. size (e.g. Lucas Method) will be a thing of the past.

Oh, good, another peeing contest

LOL - yes it was a bit of a pissing contest, but no harm no foul. Clearly homehydro and I are both passionate about hydroponics, as many are whether they be an amateur enthusiast, hardcore hobbyist, or professional grower. I'm sure we will completely agree on other topics and do battle on others. Good pick willard3...

Someone needs to make a grow setup like that. Two dudes pissing filtered water into a grow bed of some sort.

Anyways, all my questions were answered and the others that were asked by other people. So do whatever you all feel free to do in this thread.

Maybe a presidential style hydroponic debate. :P

For what it's worth, i have an outdoor hydro setup that is in a semi greenhouse (PVC pipe covered in greenhouse plastic), and I use an RO filter. It was about $250 for the 6 stage filter with membrane etc. My tap water is about 50ppm, the water that comes out of the filter is 0 PPM. This really helps me adjust the nutrients approrpiately. The britta filter or the water dispenser from safeway for example still have 200PPM.

My water bill has been the same frankly. To fill up my 55 gallon resevoir (which I do about once every week or two) doesn't seem to require much more water than when I give my 3 year old a bath or when I take one of my infamous 20 minute showers lol.

All in all it was way worth it. The filter only needs to be replaced once or perhaps twice a year and it's cheap. The RO membrance needs to be changed onc a year and it's a little more prices but not bad.

I would say 100% that if you want the best yield and the easiest time dialing in your nutrients, you need to go with RO water so that the PPM is 0 starting. Not sure if the RO affets PH but I almost never have to correct the PH in my water. In four weeks I had to correct it once.

Sounds good Outdoor_Hydro .

I plan on not using a membrane, just a 4 stage setup with DI @ the end. Might add another filter of some sort, but still doing some research.

http://4h2ofilter.simdif.com/

Check them out!

''

My first Rain water collection system was a 30 gallon plastic drum that over flowed in the First Rain. But a Free 300 gallon IBC pallet tank and about $ 20.00 bucks worth of down spout Elbow put me in business. Rain water in my area is Neutral pH and when I add my Fertilizer mix I am right at a pH of 6 to 6.1 and 800 PPM. BTW I have a small RO system that I was using and is still a Back up, But rain water is free and works great.

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