Help With Diagnosis

[ZmanArt007]

Ok, so here it goes. Monday morning, I walk into school, to my indoor tank, and discover that a shubunkin was dead. This morning, I found another shubunkin floating, the same one I saw gasping for air a day before. I couldn't see anything wrong with the bodies. This afternoon, I noticed a koi fish scratching his sides on the bottom(Flashing?). Unfortunately, I didn't have time to quarintine the fish because I was late. I am really worried, not so much about the shubunkins, but for the koi. Any ideas what is wrong?

 

[nc0gnet0]

Theres not much to go on here, and I am sure others will ask for water parameters, so while waiting for them to respond I would perform these tests. What did the dead fish look like? The one sympton you gave of the shubumkin gasping for air might suggest gill flukes, but that would merely be a guess at this point. High ammonia/nitrite levels would also cause gasping for air.

 

[DrDave]

When was the tank cleaned last?
Do you clean uneaten food off the filter elements ?
Vacuum the gravel?
Water test results?
Size of the tank?

 

[ZmanArt007]

Ok, I cleaned the filter 4 days ago.
Yes.
There is no gravel.
Test results are average.
Tank is about 500 gallons.

Update, I caught the koi fish, which appeared fine, although there were a few broken scales. (Which I may or may not have caused when I caught it. IDK.)

 

[DrDave]

Do you have good aereation? If it is not nitrates, oxygen depravation then the only thing left is Ich. Are there any salt looking specks on thier fins?

 

[ZmanArt007]

Actually, last time I checked it was last week, and it was fine, but I threw the old test kit away last time I used it. I am getting a new one tomorrow. As for aeration, that is highly unlikely. I have five airstones evenly placed around the tank. They continueously pump out air 24/7, plus the fountain supplies air. I hope it isn't ich again!!

Why do you suppose the koi fish is flashing? What different things cause it?

 

[DrDave]

Are there any salt looking specks on thier fins?

 

[ZmanArt007]

I didn't notice any. Like I said, the tank is at school, so I can't really check right now. If it is ich again, I am going to be angry.