Help! new Folwerhorn sitting at bottom.

I got a FH last week and he is currently in quarantine. He is about 2inches head to tail. He was all right till Sunday afternoon. By the evening he was sitting on at the bottom. He is not his active self, seems very lazy. Some times he is lying on his side. He is not very enthusiastic about his food like he was yesterday morning. He ate about 30% of his usual morning meal.

Temp: 25 deg. centigrade.
Daily WC 50%; He is the only inhabitant so not much bio load.


Will upload pictures when I get home.....

Havent checked the parameters, in fact never checked them till date. I dont get test kits in bangalore as they are expensive and cost more than a 20g setup so the lfs dont stock any. With 50% water changes daily I do not think there is a problem with ammonia or nitrates/nitrites.

the qurantine was seeded with water and substrate from my other tank that has been running for over 8 months.