Piscine Energetics

Hello i have a fish tank 45l with 11 fishes in it (Shubunkin , opaline gourami , honey gourami , trichogaster etc) . i added the fish a week ago and tested the water and it was fine.today i see that 2 of my Scalars aren't eating like everyone else , so i tested the water . Everything was fine except for Nitrite levels that was 3.0 - 5.0 ppm. I changed 25 % of the water and added Easy Life Filter Medium and after some hours i tested again the water quality and it was the same I also added salt

I have a pond in with my water dragon with a activated carbon filter. Is it safe for him to drink? I also used a water conditioner from petco. He is very lethargic and not eating.

My pet pike cichlid is not eating and is always staying in one corner of the tank. It is in a 20 gallon with 2 convict cichlids, 2 firemouth cichlids, 1 Oscar, and two plecos. My ammonia is 0, nitrate 0 and ph is 6.5. Water is a little tinted because of the driftwood.

What if you only have freshwater or saltwater what’s more needed

i have a pug that was diagnosed with tracheal collapse,a very severe case. its a near constant cough. he sounds like a pig but constantly. he was prescribed 3 pills and an emergeny vet gave us hydrocodine. the first few days he was getting better and the cough was less deep/violent, but tonight its very bad. my first question is can i give him turbitol, and hydrocodine together, and will having him swim for exercise help him lose weight. moving to much makes him cough so maybe a pool can help?

i also have a female cichlid that her color is faded she looks sick but is eating fine and swimming fine she is breathing a bit heavy the heat is at 85 not sure if the digitli heat is accurate or not

what is the best way to control the ph in a discus tank?

I am wondering why goldfish are settling in the far back corner of my tank with their dorsal fins down. For the past day they have been swimming much less than usual and are less energetic. The water condition is excellent.

when i was little my grandfather had a koi "patio pond" in a metal stock trough. I was wondering if it would be reasonable to do the same in a rubber one?what considerations would you consider?

after dropping discus fish pair in a quarantine tank for breeding purposes ,I add PVC pipe also for laying eggs in future , so when we found eggs as soon ?

i have a question, we recently got glofish as a gift to my mother. I bought the water conditioner, food, plants and a volcano to decorate the tank, its a 5 gallon tank so they would have alot of room to swim. But all 5 fish, just stay at the bottom of the tank, occasional moving, not to full out swimming. the swim a bit for a few seconds and hide again under the plants or filter pump, in the back of the tank. I want to know is that normal?

Hello i stared a 75 galloon 6 weeks ago nine tertas in there saturday and sunday did small water changes should i do every week or wait until tank is fully cycled? Had high nitrites levels thanks