help stingray died, dunno whats going on!
I posted a bit ago with the fish just dying over the course of 2 year without warning. Today I found my stingray died. I don't know whats going on. I do water changes over the course of the years (every week) and there is nothing wrong with the water. the water is normal temp (84-86F) for the discuses and stingray. Like I said today, he died. theres no reason why he should of died. He ate well with a varied diet, tank water parameters are normal, I did a water change earlier this week, last time I had my hands in the tank was Wednesday, which I washed correctly (first with soap, then cleaned off with water for about 2min) fish do look stressed. I'm going to do a almost full water change, and I'll take a ride up to the fish store tomorrow to see if they can also do a full water test.
there are 2 filters, a sump which is cleaned once a month and a canister filter which is cleaned out weekly from the debris of the live plant, and carbon changed about every 3 weeks. The canister pumps back to a spray bar I made at the bottom of the tank so the stingray always got clean water, plus it moved all the sediments. the fish are fed good with 3 different foods including pellets, flake and frozen. The stingray got live food - worms and ghost shrimp. I also add some chemicals including discus essentials, black water extract, and kent plant chemicals (im 1/2 of their recommendations) plants are doing just fine.
Stingray like I mentioned did not look sick or anything, did not have a curling going on the back part or anything. He did though act a bit frightened this morning and when I came by was swimming to the top a few times then back around the bottom, but I seen him do that alot - swimming to the top of the tank, then just sink back down and continue on.
the other fish are stressed, I can tell, they are really dark (a few of the discus) not sure because of the death or something else. No diseases I can see, all the fish eat.
Only thing I can think of is something, somehow got in the water, and I don't know what.
I'm lost on this one.