I have Juwel 125 tank, for a long time I have not tested it for ammonia.I could not see all my rummy nose tetras (one missing) and I tested ammonia and it was around 0.25-0.5 ppm, nil nitrite & nitrate. I did a WC 40% last Sunday.I added an old circulation pump to increase flow. No new fish added recently and not very heavily stocked tank. I did a 50 % WC after tested tap water for ammonia (it was nil) and added overdosed Seachem prime to detoxify ammonia as instructed on the bottle ( I use it for WCs as well) I will keep WC and will add Tetra Safe start to help the beneficial bacteria.
I dont do substrate cleaning as most of the tank is inaccessible and feed the fish carefully. I cleaned the media at the last WC,only the top bit though.(There are 2 compartments of media I clean the top one every other week and bottom in every 6-8 weekish with tank water.It is Juwel's intank filter system.)
The fish dont look stressed but as I have said at least one missing, I cant see one of the Ottos too but they are not very easy to spot, I thought it might be just hiding.
When I did WC 2 weeks ago, I forgot to add Seachem prime when did the WC and turned the filter on but I realised what I did in 30 seconds and stopped the filter and added SP to the tank directly.
Any suggestions to find the root and advice how to deal with the situation.
I dont do substrate cleaning as most of the tank is inaccessible and feed the fish carefully. I cleaned the media at the last WC,only the top bit though.(There are 2 compartments of media I clean the top one every other week and bottom in every 6-8 weekish with tank water.It is Juwel's intank filter system.)
The fish dont look stressed but as I have said at least one missing, I cant see one of the Ottos too but they are not very easy to spot, I thought it might be just hiding.
When I did WC 2 weeks ago, I forgot to add Seachem prime when did the WC and turned the filter on but I realised what I did in 30 seconds and stopped the filter and added SP to the tank directly.
Any suggestions to find the root and advice how to deal with the situation.