Whitish stuff on koi

[CaptainJ]

I have a 1yr old little koi who started showing signs of illness (isolating, sitting either at the bottom or hanging near the top, clamped fins) after my goldfish lost their minds spawning. At the time, he was being held in a temporary 55gal tank while I was doing some emergency pond renovations (dog dug under the pond and collapsed it inward). The goldfish spawning (I have 2 males) severely increased the ammonia and nitrate levels in the tank which I have been able to bring back down to 0's for both. The other koi seem to be doing fine, but this one has severe reddening in his fins and just recently developed these patchy-peely looking spots. I don't know what it is or how to treat it and I could really use some help.

I really hate to keep my koi in a tank as I know they need way more space than 55 gal. I've reduced their feeding to once every third day and immediately scoop out anything that hasn't been eaten in 3min. Everyone else seems to be okay, but the one koi is just not looking good. I tried to do a scraping, but he just wasn't having it. I gave him a quick salt dip (2min in solution of 3oz per gallon of water) and I just don't know what to do next.

Any help is appreciated,

-J

 

[Lisak1]

How many fish are in the 55 gallon tank?

A salt dip is a good start for helping a fish heal, if the problem was caused by spawning. But it could be ammonia burns, too which is more difficult - outside my expertise for sure.

 

[CaptainJ]

At the moment, I have 6 koi in the tank. 2 4in., 2 6in., and 2 11in.

Do you think ammonia burns could cause that white stuff on his body? Or perhaps is it something that is affecting him if the ammonia weakened his l immune system?

 

[CaptainJ]

Update:

I was able to scrape and scope a different koi and found a trichondia and what looked like costia. I've moved said koi to -another- bucket with increased salinity and added a dose of parasite remedy. Fingers crossed.

 

[CaptainJ]

Update:

Finger crossing didn't work. The infected koi died. Did a water change for the other koi and for the goldfish and washed all equipment that I could down with 140° F water. The fish that I had a picture of is looking a little more ragged.

Would really appreciate some help,

-J

 

[WaterGardener]

If this is actually costia, I think the recommended treatment is formalin and malachite green. Proform C is probably the most common product used. But it can't be used with salt, so be sure your water is salt free.

This is from Sacramento Koi:

Treatment Procedure with Malachite Green and Formalin
Malachite Green and Formalin should not be used when the salt level in the pond is higher than .1% unless you know for a fact that the pond water is very soft. If the pond water is hard at all and the salt level is above .1%, the use of formalin can severely burn the gills of the koi. Malachite Green & Formalin can kill the beneficial bacteria in the biological filter, so if possible, the filter should be bypassed for at least 8 hours during use. Malachite Green & Formalin can kill plants so, if possible, all plants should be removed while the pond is being treated and the plants should be treated with potassium permanganate separately before returned to the pond. (To treat pond plants for parasites, mix up a solution of 3 tablespoons of potassium permanganate dissolved in 12 gallons of water. Allow the plants root ball to dry out slightly and then completely submerge the plant root system in the solution for 2 hours.)

• To treat ponds up to 1500 gallons. Measure out enough Malachite Green & Formalin to treat the whole pond at a dosage of 10 ml per 100 gallons. Drain 50% of the water out of the pond and then add the Malachite Green & Formalin to the pond. After exactly 2 hours, refill the pond as fast as possible to its normal level. You must be able to refill the pond within 45 minutes or you risk the chance of burning the fishes gills. Perform this treatment 3 days in a row. If you have costia we recommend treating one more time on day 5. If the pond is being refilled with city water remember to add dechlorinator to the water to remove any chlorine in the new water. This technique is very effective because the parasites are exposed to twice the dose of medication for 2 hours which is usually enough to kill them.
• To treat ponds over 1500 gallons. The above treatment cannot usually be performed on ponds over 1500 gallons because it takes too long to refill the larger ponds. In this case we recommend performing a 25% water change before each treatment. After the pond is refilled to its normal level, add the Malachite Green & Formalin at a dose of 10 ml per 100 gallons. Treat the pond 3 days in a row. If you have costia we recommend treating one more time on day 5. If the pond is being refilled with city water remember to add dechlorinator to the water to remove any chlorine in the new water.

Good luck and I hope you don't lose any more fish.

 

[Lisak1]

I'm sorry to hear your fish died. And yes, ammonia burns could leave the fish susceptible to other types of infections. Btu I believe ammonia also affects their gills, making it hard for them to take in enough oxygen.

That's a lot of fish in 50 gallons... any chance you can get some additional tanks going? Even a kiddie pool outside would be better. How big is your actual pond? Just for general information, koi require lots of space. Many will tell you that you need 1000 gallons for just the first koi. They are heavy waste producers.

Here's a chart that illustrates the difference between koi and goldfish biomass in a pond:

Koi Length and Weight - Ammonia Produced, and Waste Produced

This chart also lists koi weight by weight and how much ammonia and waste they produce. Koi get heavier as they grow and produce more ammonia and waste.

russellwatergardens.com

 

[CaptainJ]

Thank you, I'll try the formalin. I ordered it, but unfortunately the first fish died as well. I'll see if it helps the others when it gets here.

As for stuffing a tank, I am guilty and I suppose I'm seeing the judge jury and executioner here. Since my first post, I was able to find a 10 gal bucket for each fish and have just been doing consistent water changes, aeration, and monitoring temp and levels. This was really only supposed to be until the pond wall could be repaired. The pond is close to 2000gal. I checked out the link you sent @Lisak1, and we are definitely going to be expanding the pond this fall. Here's to hoping we don't lose anyone else. ):