Dead Discus... HELP...

[iKon]

Hi guys,
Im just wanting to know what could be the problem. Here are the details.

*Fish were all dark and the bars were showing
*Fish were very very skitish and hiding
*Fish started to lay on there sides and seemed to have no energy.
*Fish started to lose there slime and skin started to peel.

This all started to happen after i purchased a second hand filter that was in use on a tank with discus. It was disconnected from there tank and connected and running in my tank in less then 1 hour (still full of water). We did lose 1 red turq that didn't look very good when we got it before this, but it was put down to stress.

Our pH was 6.8, GH was 60, KH was 40, slight amonia, no nitrite or nitrate.
Temp was at 29degrees. Tank was a 4x14x18 with external filters and an under gravel(2x powerhead 2x airstone).

Fish that were lost. All around 6cm to 12cm
2x Blue Diamond
1x Royal Green
2x Blue Turq
1x Red Marlboro
1x Solid Red
1x Red Sun Rise
1x Snowflake
2x Red Spotted Green
1x Red Diamond
2x Briliant Green
The only 3 that survived in the tank were the 3 smallest fish 3x Snowflakes (5cm)

So now we are trying to figure out what caused it, any idea's?????

Im from Melbourne, Australia, if anyone has any nice looking cheap discus to help me get started again can you please let me know.

Email = piercedpunk69@hotmail.com

Also i have fully cleaned out the tank, taken out the under gravel filter(was told this could aid bad bacteria) and cleaned the gravel, replanted all the plants and done 4x 90% water changes.

Please i need some help, need to know what it could have been so it doesn't happen again, have 2 pairs that look like they are going to start breeding soon. Don't want any stuff ups.

[Carol_Roberts]

How long was the 2nd hand filter running on your tank before the discus got sick ? How fast did they die?

[iKon]

Well it was about 2 days before we noticed anything was really wrong. Becasue with the external filters there wasn;t much of a current in the water, we thought they were scared of the canister filter because of the current in the tank. When we noticed 1 or 2 getting really dark and starting to lay on there sides we knew something was extremely wrong. We treated the water with melafix as we were instructed by the local aquarium.

I share these fish with my mother and she is at witts end, all together we have spent a lot of money on our passion, and if this happened again we will have to sell all tanks and the remaining fish(if any survive this time).

[Carol_Roberts]

That's a big loss! 14 of 17 discus. (Also that's a lot of discus to have in a 50 gallon graveled, planted tank)

I'm guessing something bad came in with the new filter. IF it was a sealed canister with water and no oxygen it could have been full of "bad" bacteria by the time you got it running on your tank. Anyway those discus from that one tank are dead.

Do you have other discus tanks? If yes, were they affected?

For best success with discus I would get rid of the under gravel filter. I don't like canister filters either. They quickly die and go bad if the power is off for even a few hours.(no new oxygenated water).

I'd try a bare tank with hang on the back power filters. Sterilize everything including the heaters. Cycle the filters with pure ammonia. I'd place the 3 survivors in a 29 gallon by themselves for now. In a few weeks when the filters are fully cycled. I purchase however many new discus you can afford (6 - 12). Keep quarantine and don't mix the new and old for 6 weeks. Put your least favorite new fish in with the 3 survivors. wait 2 or 3 weeks for illness to surface.

[iKon]

well within 45mins i had the filter connected back up in my tank... i thought the bacteria could live for at least 1 hour.

we have 3 tanks 4x14x18(main planted tank which probs started), 4x18x18(larger fish were put into this tank but some died. bare tank with a fluval 304 canister filter) & 2.5x14x18(where the smaller fish were put and most died bar the snow flakes and a red marlboro. box filter and sponge filter).

most of the fish ranged from 1.5" to 3.5" so they weren't that cramped in the tank, there was plenty of room.

i also have a 12" black ghost knife fish and 4 weeks before all this happened his skin was peeling so it may have been in the works for a while. im not sure, he is ok now.

[Carol_Roberts]

So, if it ran through all you discus - even ones who were originally housed in the two other tanks (after you moved the sick ones to those tanks), then it must be a disease rather than a heavy bacteria load from the canister filter. Your survivors may have been exposed to the disease in the past and had antibodies? Just guesses.

I'd sterilize 2 tanks, filters, heaters, etc. and do a fishless cycle before I spent anymore money on discus. . .

[ping]

Hi iKon,

Sorry for your lost. Rod Coleman is from Melbourne too, he might have some discus for sale.
Here is his detail http://forum.simplydiscus.com//index.php?board=;action=viewprofile;user=Rod+Colem an

You can contact Rod Lewis too. He is in Brisbane but he can ship discus to you. Yeah, we have too many Rod ;D. Here is Rod Lewis's detail: http://forum.simplydiscus.com//index.php?board=;action=viewprofile;user=Rod

I agree with Carol, you have to sterilize, heaters, filters and tanks before buying discus.
And keep discus with discus only ;D in bare bottom tank. :)

HTH,
Ronny