New to keeping bettas, but do have some fish keeping experience. I have read through the threads looking to identify a similar or same problem and not sure I have found it yet so here goes:
Got our new boy a couple of weeks ago. Had put him in a much larger tank with some other tropicals (neons, rasboras, corys and a featherfin). He turned out to be rather agressive and picked on everything he could find in the tank, even the smaller plants !
So to solve this problem, we got a smaller, dedicated tank setup for him (19L) and migrated him across to his new home where he was fine for the first day. The tank was setup for about a week prior to putting him in there and I made sure to use water conditioner (as always) and filter boost (active carbon filter). We thought this new tank may be better as there was far less current from the filter and less bubbles from aeration to worry him.
Then the day before yesterday he spent most of the day at the top of the tank - not so worried as he needs normal air. He was still feeding on his favourite - bloodworms.
Yesterday and today however he has spent nearly all his time at the bottom of the tank. He isn't on his side and will swim when disturbed, but isn't letting his fins show their true glory. Also he refused to eat these last 2 days.
I've tested the water - no ammonia, no nitrite, no nitrate, no chlorine and acceptable hardness and pH.
Water temp was a little low (23 degrees) and have risen it gently to 27. Still no change !
He's been in this tank now for 4 days and have completed a 50% water change today. Tank is filtered and heated with live plants and some dark corners for him to hide.
He's not actually sitting on the bottom of the tank in the gravel, he's hovering about 1cm above it and is the right way up (i.e. not on his side and level).
Looking for some help here please as the first betta we had was actually sick from the pet store (although he didn't look it) and died within 2 days of being home from a major infection (causing havoc on a well established tank - now fixed) and my son absolutely adores 'his little red fishy friend'
Could this be he is adjusting or something more sinister ?