If RO/DI water was dangerous to fish then a good portion of reef keepers would have dead animals and fish. You should replace the trace elements though. Another option is to use only a portion of RO water mixed with your tap. www.drsfostersmaith.com has a few fresh water RO/DI replacement supplements for a good price. I use a 6 stage RO/DI system and use what is called "PMDD" ( Poor Mans Dosing Drops) trace elements. All it is, is a dry hygroponics fertilizer that you mix with water to get the correct concentration and it has directions per gallon dosage. It is very inexpensive because it is bought in bulk and divided into packets. If you want I could give you a link to the person I know who runs a fishkeeping forum group and sells it way under commercial price. It has all the essential trace elements for fresh water tropical fish and plants. Kent and Seachem also have quality commercial supplements. You shouldn't use just plain RO/DI water. Without supplement the water will take it's toll on the fish.

Woe: Yes, please. Do post a link, and thank you.

Logic kept telling me that pure water with trace mineral and other essential elements replaced would surely be better than what is dumped into municipal water supplies these days.

BTW: If you were referring to Equilibrium, Kensfish.com beats F & S on both per item price and shipping costs.

Here is the link. He has updated stuff that is sold. it has been a while since I was on that site. Very good deals. If you have plants, the starter pack will last you years, including the PMDD. Also a great forum, worth joining for sure.

Here is a link that might be useful: PMDD & ferts

Hi
I use pure or Ro, rarely rainwater for tetras. Have some Cardinals since Feb 01 Still have 12 of the original 15.
Also still have the four Clown loaches but they're tough so I don't count them.. I even use it on my swordtails of those I keep in tanks. don't even add salt.
As a guess I'd say I have between 3 and 4000 of them so I'd say it must not be too dangerous lol gary

Thanks for the link Woe, and Gary; both of you- for your reassurance.

I'd like another opinion from you, and anyone else who cares to pop into this discussion.

I recently bought a bunch of small FW fish, shipped to me from out of state. They were fasted, then bagged on Monday evening, shipped on Tuesday, and I got them on Wednesday morning.

Although it was contrary to my own past practices, I nevertheless followed the seller's instructions and netted them out of the bag water, directly into a tank. By that evening, 2 were dead, and over the next few days, close to half of them were. The remaining fish rallied and are now all fine.

My USUAL routine is to to float the shipping bag, then release the fish into a 1 gal. glass tank, floating in the quarrantine tank, and adding about half again as much tank water as was in the bag, along with a small airstone.

Then, over the course of several hours, the water in the small tank is removed and disposed of, as quarrantine tank water replaces it on a 2-1 ratio: 1/2 cup out, 1 cup in.

The glass tank starts to sink as water is added of course, but stays enough afloat to keep the fish from swimming out, and the quarrantine tank water keeps the glass tank water at the right temp.

By the time virtually all of the original bag water is gone, I net the fish out and into the quarrantine tank, and rarely have losses.

But I was cautioned not to do that becoause, accordng to the seller, the fresh water added to the bag water would kill them.

I am confused. If they are alive and swimming in the bag water; why would fresh water react to it so severly as to kill them?

And yes, of course I know better than to ever dump bag water into a tank.

Opinions please?

In that link I gave you there are also many articles written. they are in the left column "Published Articles". There is one about acclimating fish into a new tank. This is how I do it. Basically at 10 minute intervals I add a % of water from the QT tank to a gallon container with the original water from the pet store or shipper. Before adding water from the QT each time I dump that same % out. So, In the gallon fish container with the water from the store I slowly pour, say 8oz. in. Then in 10 minutes I remove 8oz. from the container with the fish and replace it with 8oz. of "fresh" water from the QT. Continuing this regimen for about an hour until most of the water in the container has diluted the "shipping" water. Then I slowly pour the water from the container into a net until the fish are all out and put them in the QT tank. Shipped fish, especially ones that have been bagged for long periods of time are weekend quite a bit. The stress of changing dissolved solids so drastically is probably more deadly then water temp. or pH. the combo of all 3 can put them over the edge. I like Drs fosterSmiths fish shipping policy and guarentee. I haven't used them yet, but have considered it. Man I miss my tanks. I can't wait to settle into the new home and set a couple up.

Woe:

You have described virtually the same method I use, for the same reason; to lessen the shock of sudden changes in water chemistry.

Try floating the acclimation container in the QT tank sometime though. It really does keep the temp in the acclimation container the same as in the QT tank.

I agree that temp isn't the only factor, but eliminating any temp. change when they are finally released into the QT doesn't hurt either.

Thanks to your kind follow through, I have lots of reading to do.

So many interesting things to learn; so little time. (Sigh.)

The acclimation container starts with only the same water that the fish are shipped in. Then I slowly pour a small percentage of the QT water in that to start. It does the same thing as floating the bag. I use an old tupperware iced tea pitcher that is 70's orange. The darkness helps with the stress factor also. I also feel that fresh oxygen is important which who knows if it has been exhausted by the time you get home. i know a LFS owner who ships fish and I think he pumps oxygen into the shipping bag or container before sealing it. The other reason is less stress from movement on fish. I used to float the bag the standard way and never had any more problems then this way. Like the saying goes "If it ain't broke, don't fix it"

Woe: We are still on pretty much the same page on acclimating, and as Kordon bags gain in use, floating may become eventually become thing of the past, which is good I think, because the fish suffer far less banging around in transit.

But when I do float a plastic bag, it's in a very dim light, just enough to let me see what I'm doing. Then, it's only room lights. They don't get under tank lights until they have been out of the total dark for several hours.

But I also don't always float. If the bag feels close to the same temp as the WT water, I do exactly as you do: release them into the small container, and add some QT water.

And, of course, if they are in Kordon, they can't be floated at all, regardless.

Remember that if you are drinking this RO water too, that you will also want to add some minerals back to it. Liquid trace mineral drops are a good way to go and so is a squeeze of fresh lemon juice.

Here is a link that might be useful: Trace Mineral Drops