460 Gallons is way to small for raising more than a couple koi.. I would not use any algea killing products as its poison to the fish and since your pond is so small the concentration of the chemicals could kill them all. The dechlor is fine for the exchanges but I wouldnt do anymore 300 gallon ones.. You need to test for Ammonia and Nitrite and make sure those levels arent skyrocketing and check PH as well.. also if you have lots of algae add plants and maybe even starter bacteria, and look at cleaning out your filter.. what else does your pond have in terms of UV, pump, airation, filter, skimmer, drain? You also say you saw a fin stuck in the algae.. was it a fin or a whole fish? that didnt sound good..

I regularly clean the filter and pump and did a test on the water quality and everything is at a safe level (ph, nitrate, nitrite, ammonia, etc.). I added a water lily a couple of weeks ago and it is growing. I have pickeral, dwarf papyrus and corkscrew grass growing in the pond also. I have an aerator on constantly along with a pump and fiter. The filter is one that remains in the water attached to the pump.

I guess we could look into making the pond bigger, but that just seems like a mountain I can't climb up so soon after buying a new house (my first one). I'm new to this (just bought the house a month ago and inherited the pond with it)and have been "taken" by quite a few stores around the area. Some folks say that the pond is a good size and others say it's too small. The owners left us info when they moved and the smaller koi are offspring of the larger ones.

Any ideas on why they are so inactive?

As far as the fin--I pulled it out of the algae and it was a fin-not a fish.

With all your koi you will have to expand your pond, can you imagine say 8 24inch koi in your pond? They would barely be able to move. If your readings are correct and ammonia and nitrite is zero then something else must be going on.. hard to say without seeing your pond as every pond is different and remedies vary from pond to pond.. some people think the same remedy for one will do the same for another which is not true. If you can post a pic or send one to me that would help.. kevip@excite.com I wont say I am a expert but I have made every mistake already and have learned a great deal. I also have my koi experts that I use to help for any advice as well.. I would say they have helped me the most as they not only sell japanese koi but are also koi vets and not just some person with a cert. If you had a spawn your koi would be dormant but there should be signs of the spawn like eggs and a ammonia spike. The fin in the algae is not a good sign.. is one of your koi missing one? Besides water chemistry another thing could be a predator.. if you had an attack, bird/snake.. koi would isolate for sure.. anyway a pic would go a long way in helping to troubleshoot more.. also what kind of water test are you using? If you are using some kind of test strips.. throw those away and buy a good kit with test tubes and the chemicals.. its not hard to do the test with these kits if your not already using them.. congrats on the house.. I am also in my first house as well and I know its alot of work.. you can see my site and pond too on my website.. I will try and help the best I can with the resources I have but bottom line at some point you will have to either remove some fish or bite the bullet and expand the pond..

Here is a link that might be useful: our site and pond

I sent some photos to your email (before and after). If this helps, let me know...I'm off to go talk to some folks at an aquarium store--they have about 12 2 foot koi in a pond when you walk into the store, so I hope that they at least know a little something...

We had a similar problem with our koi suddenly "hiding." A friend suggested that our pond might be getting nocturnal visitors, such as raccoons, making the koi nervous. Our pond is netted, but obviously the koi don' know that.

My husband started...ahem..."marking territory" around the perimeter of the pond, and that seemed to work! After a few days the koi became active again.

Don't know if it was coincidence, but it didn't hurt.

The exact thing happened to me this week! The day after we cleaned the filters and skimmer we could not find our largest koi. 2 days later a second koi is missing. I am so attached to these fish I could just cry at the thought of them being eaten by a snake or bird. We put a net over the pond. they both disappeared at night. I have about 13 more fish. I hope they are all accounted for in the morning. I cannot see the bottom, it is 5 feet deep. Maybe I scared them while I was cleaning and they are hiding on the bottom. I hope we both find our fish alive!

They've finally reappeared, but last night we had a predator of some sort thrash the pond. I'm not sure if it got any fish yet, as the pump and filtration system was wrecked and I'm waiting for the algae to settle just to see what I am dealing with. I guess we're back to square one and will just have to wait and see if they decide to come back out again. It's true, you get so attached to them and it's awful to think that some may have been eaten last night. Uggh!!

kayokayo: I'm sorry you've had so much trouble with your pond! Sounds like racoons got in it and trashed it.

The in-pond filters attached to the pumps are not the best kind to use. You'll find that an out-of-pond filter will work a lot better and you will get much faster results. As a matter of fact, I would go so far as to say that the in-pond pump filters really don't work much at all to clear your pond.

An out-of-pond filter is so easy to make. You just put a hose on the pump that takes the water up and out of the pond. Let it fall through a container of some sort filled with media (pure bbq lava rock, nylon bath scrubbies, etc.) and out the bottom back into the pond. You can use a large decorative pot for this, that will look good at the side of the pond, or a plastic barrel and hide it.

Since you are trying to clear a bad pond, I would suggest using something dense at first, like quilt batting, and cleaning/changing it often, even daily, until the pond is clear. It should only take a few days to clear it. Then replace the quilt batting with with something bigger and porous.

A large decorative pot is great for a filter and can make a nice fountain too. Drill holes in the side near the bottom. The outpour hole needs to be four times the size of the intake hose or it will fill up faster than it drains and run over - losing a lot of water. Then just run the hose to the top of the pot and let it run straight down into the pot and over the media and out the bottom. The water has to run through the pot to be filtered before running out the bottom and back into the pond.

Thanks so much for the advice, runningtrails! We have new koi from the latest spawn and will need to expand our pond very soon. The filtration idea is great. We want to expand, but do it ourselves and not overdo it. I've introduced barley into the pond and it seems to be doing a great job of keeping the pond clear. I just cleaned the filter and pump today and taking the pump and filter out caused a lot of algae to disperse back into the water and cloud it again. I think it will be clear in a day or two. Now that they are active again, I just love watching them feed and swim around but don't like how unattractive the filter looks at the bottom of the pond. I never thought I'd be keeping koi, but I've learned so much and fallen in love with them...What a nice "inheritance" we got when we bought our house!!

Since you are contemplating building a new koi pond, let me introduce you to a web site that is dedicated to koi keeping. Koi are not at all like goldfish. they can get VERY large and need a lot of space. Each koi needs a bare minimum of 300 gallons, with a pond no less than 1000 gallons. They need a pond bottom free of rock since they are such heavy waste producers. They need filtration that is much more efficient than that you'd see on a goldfish pond or a water garden. You're lucky though....you have time to find out how to do it before you dig!! And you have lots of koi clubs in your area to help guide you.

Here is a link that might be useful: koi shack

I've had my koi ponds for almost 20 years now but it wasn't until this last month when I put in my third one, that I hooked up a UV sterilizer to the filter. WOW! What a difference it made. Just overnight my water became crystal clear! I could see every detail on every fish all the way down to the bottom (4 feet down). If you want to avoid the stress of not knowing and worrying, I'd suggest you invest in this unit. You'll get way more pleasure out of watching your fish as well. Don't forget though, if you can see the fish, so can the preditors. So be sure to give them plenty of plant coverage or hiding places for protection. Good luck!

My biggest threat to the fish is a big white bird. I know he sometimes gets goldies from the settling ponds, may be cruel but I do catch some of the goldies and put them in the settling ponds.The dogs do a good job of keeping everything else out of the pond,usually. I have had a family of coons visit but the dogs treed them and they sure wee cute but i locked the dogs up and watched them leave. My yard has a 6 foot fence around it due to codes and pools so Im not that worried about animals even though they climb the dogs are very viligent about the pond. All I need do is say birdie and off they go looking for birdie all 5 of them. I have placed pvc pipe in the pond as tunnels in fact one tunnel is an 8 inch x 10foot piece that they just seem to love, Didnt want to worry about koi getting stuck in it. I did notice that in the settling ponds that the goldies are more aware of movement then in the main pond they hide more and only venture out when I feed them by hand and prob at night I have 2-3 goldies and maybe 10-12 flatheads/silversides (sold as feedes) in each settling pond. My pond is about 6000 gal all total the main pond is 3 foot deep and the settling ponds are from a foot to 3 foot deep stream is 14 inches deep. I really have not seen any sign of animals messing up the pond other then the dogs making trails thru the plants