Thanks a lot for your replies and sugession. I will work accordingly fro sure.
[quote=Squawkbert;333374]1) If that substrate has been sitting w/o any fish or inverts in the tank, it is no longer cycled, so plan on doing a fishless cycle or using a filter from a cycled tank or choosing your initial fauna carefully.
[quote]
The tank was really overstocked with fishes for last 4 months. So it's having a huge bacterial colony to support a huge bioload. I stocked arround 30 fishes in this small tank.
For the background, I am completely agree with you all. But I have done a one time permanent mistek.

While setting the tank up in past I paste the background with silicon glue. So there is no way that I can change it now.
