New fish hides at bottom

[AquaNewb]

What's wrong with this stupid fish? 24 hours after acclimation, it just sits at the bottom. I think it is breathing quickly, but it is a small fish so maybe it is normal. (1 inch)

At first, it swam around tank with more gusto and tried to eat things like dust suspended in water, and would come to top of tank as if it was going to be fed. Then less and less of this until now it sits nearly motionless under plants. This makes me think it is water problem...

But, nitrites, nitrates, and ammonia are definitely zero.
Maybe water flow too strong? It's an old 10-20 gallon HOB filter, turned on to half strength
Fish was acclimated by floating 15 min, then filling up its bag another third of remaining space with tank water every 5 minutes, 3 times

 

[ghandi555]

I had this with a fish but it was just being a bit grumpy on the odd day I think. All my water was spot on... feeding but not over feeding. He sat on the bottom for a couple of days, now he is very happy and loves life. But I think fish can have their off days. If it continues to do this then it is stress but can be from a few things

 

[BBradbury]

Aq...

If the fish is acting abnormally, it's a water problem. Once the tank is properly cycled, you have to remove most of the water and replace it with tap water treated with an additive to remove chlorine and chloramine. This water change should be done every 4 to 5 days for a small tank up to 30 gallons. Larger tanks can go a bit longer between water changes, but still need at least a 50 percent change every week or so.

B