almost gave up

[slp]

About 3 weeks ago my 75 gal tank, with 8, 5-61/2 inch discus went south. Since that time I have lost 5 of the 8 original fish. I think it is starting to come back under control. I currently have a sponge filter in the tank. and have discontinued use of the canister filter. I plan on thoroughly cleaning it with bleach before putting it back into service. I think I had a serious bacteria bloom that was causing all my problems. Hopefully I have it licked. During the worst time (had 2 of the five who died do so in the same day), I thought that if they all died I would clean the tank and all the filters and stock with a different kind of fish. My wife talked me out of it and encouraged me to restock with new discus. I think the last three might survive. They still have a long way to go to recover but I am hopeful,

I will restock regardless but it will be at least a couple of months. I am currently looking for a quarantine tank since I don't want to put either the new discus or the ones I have in peril. Can I add a sponge filter to it that I will seed from the main tank?

When I do add new fish (after quarantine ), can I use fish from more than one breeder?

[Champion Discus]

Sorry about the lost @slp.

So what did you do diffferently that you believe to have caused the tragedy?

How often were the canister cleaned when it was in use?

I personally believe sponge filter are sufficient, and buying a bigger volume sponge than your tank will be more effective. I currently use all sponge filter in my tanks, but doing w/c are also of the most important I believe in any filter that you use.

My theory is theres micro organisms good and bad that the eyes can't see basically get transfer back and forth into the tank and never leaves without proper w/c removal.

[Champion Discus]

In my opinion, I believe mixing discus from multiple sources has its pros and cons.

I know owning discus from different importor/breeders are also part of the excitement in this hobby.

I believe that all sponsors here import from high quality/sanitized world class facilities. But when in doubt do use separate tanks to house them. By taking cautious QT procedures I believe housing no more than two different sources should be fine. Ask importers for a copy of their health certificate on their products and read up on their QT process to ultimately come up with your decision.

Now this is my opinion.

[slp]

The reason I am blaming the problems on the canister filter is that it started right after I cleaned the canister. It had been in use for over a year with it being cleaned about every 6-8 weeks. Never an issue until this time. Didn't do anything different but I did notice what appeared to be a extra large amount of gunk in it, which I tried to clean out. The water started to turn very cloudy and the fish started to dart around running into the glass.

[Champion Discus]

@slp

If there was no other known difference, this gunk might be the factor in your dismay.

Can you describe this gunk. And as you've observed after this gunk dissolved and caused cloudy water. I can only conclude that somehow it affected their lungs. But then again not all your discus passed. Could of been luck and the strongest 3 out of the 8.

We're the discus passing all in the same day?
But surely sounds like this gunk played a factor since your other cleaning didn't display this kind of affect before.

[alron2]

I cleaned my canister filter with very strong bleach solution and it destroyed my gaskets in it. Be careful.

Ron

[Filip]

Mixing sources always poses a thread of cross-contamination issues . I would rather stick with your current source .
BTW ,you want to start sterile (tank ,water, filter, equipment) with your new fish so using a filter out of your current discus tank beats the purpose of quarantine.
Just ask for a seeded sponge from the vendor you are buying your new stock , and do lots of WCs in the first month.