Help I lost one!

[fishyj]

Hi all, Iam puzzled, one of my juvies died on me. I use aged water, with prime. I thought he was eating but when I came home from work he was at the surface breathing rapidly. Nothing new has been added to tank, 20 to 30gallons daily water change. I believe this is the one that would darken while I would clean the tank. I read prime can give a false ammonia reading. The other discus seem fine, cory cats and bn are also fine. The only other thing is the rummynose are not as red in the face as usual. the fish had no spots or anything on its body at all, which makes me think its a water issue. Any ideas?
Tank temp 86
Nitrate 10
Nitrite 0
Ammonia .25 but am using prime
Ph 6.8

[nickmcmechan]

Prime doesn't necessarily give a false ammonia reading

it converts ammonia to ammonium which is less toxic - but most test kits measure both

it also breaks the chloramine bond and then detoxifies the resuting chlorine and ammonia

when do you measure the ammonia - immediately after water change? what is the reading after an hour? what are the readings of the source water after 24 hours? what test kits are you using? what is the total tank volume?

[fishyj]

The ammonia reading was after 24 hours, using api test kit, and tank is 125 gallon. The only thing I did was change the filter floss in the tank on my hob.

[aquadiva]

The ammonia reading was after 24 hours, using api test kit, and tank is 125 gallon. The only thing I did was change the filter floss in the tank on my hob.

Sorry to hear that you lost one of your Discus. When a tank has any ammonia reading, it would have been good to leave that filter floss in the HOB. Likely it was building some good bacteria up on it which is essential to cycling the tank. How many filters are on this tank? Always leave one with some good bio build up on it. Change them one at a time, maybe a week apart.

Anna:sun:

[fishyj]

I have 2 filters going but now I have noticed some one gill functions I going to post in other section.