Question
HiRobyn,I hope you can help. a couple of my koi had some white cottony spots on them which looked to be a form of ick.I put the salt level up and it seemed to have taken care of it with a couple of them.I did notice that one 12" scaleless koi had a different problem it looked like he had algae on his body and welts, he looked bruised and his top rear fin was almost gone.he did die yesterday and today, a perfectly normal looking one died. my son and I looked in his gills and noticed that they weren't pink or red, but two toned brown and red. when we looked further into the gills they looked like they had dirt in them. I just found out I have tannis in the water from the dirt in the bottom of the pond which the fish created by knocking over some large plants. I have some large koi about 24" and they knocked over a few plants. But as you must well know, when you start reading you see a lot more than you imagine. now i'm starting to see the fish going to the waterfall and stay under it for a long time and also jumping out of the water. all of these things seem to be all differen't diseases,and I'm very confused. the pond is approx 3800 gallons and I have about 35 koi. the chemestry has been perfect since the begining of the season. [email protected] to 8.0 amonia @ 0,nitrates @0. just 11/2weeks ago I put plant food in the pots, and that was the only thing I did differently.My son was reading the plant food pack and it seems to contain a form of nitrates in it.I live in NJ my phone # is 732-829-6686 if you need to call me. I thank you very much for any help you may be to me.
Tony  

Answer
Ick is usually not cottony.  That is normally fungus.  Salt will also kill fungus.  It is common for fish to get physical injuries, often from spawning and to have those spots grow fungus and/or algae.  My koi, Colin, right now has algae growing on him over sores that look like someone ran a cheese grater over him.  I treated the pond with KoiZyme but it didn't seem to help in his case.  Pots being knocked over and having dirt in the pond shouldn't be a problem for koi who naturally would live in ponds made of dirt.  I'm not sure why you saw dirt in the gills; that's strange and perhaps a question for a person more familiar with koi (see koivet.com for example).  Tannins come from leaves and other vegetation and would not be found in great quantities in dirt.  

Fish gasping and jumping may indicate many different problems that result in a need for oxygen such as low oxygen levels (from heat or decomposing debris among other things), parasites (which inhibit the fish's ability to get oxygen), poor water quality, and infections.  I suggest that you contact your local koi club.  They will often do a scraping of your koi for you and see if there are any parasites or obvious diseases that they can treat.  Otherwise, the salt was a good idea as is adding extra aeration and doing water changes.  Did the koi release the plant food when they spilled the pots?  That would only be a problem if they then consumed some, or it wasn't pond-safe fertilizer.  Most pond fertilizer doesn't have nitrates so maybe you have the wrong stuff.  Don't use that until it's straightened out.  Good luck!

Robyn
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