hi all, i'm looking into making my own background and have done lots of research, think i'll be using the polystyrene method and coating in cement. My first question is, obviously polystyrene flats so how's the best way of fixing it to the tank with out removing all the water (i've read about sealants but am i right in thinking the tank would need to be empty to do this !!) ? Secondly i'm looking into purchasing an external filter, what would all you good people suggest for a 100l tank ?
thanks in advance
thanks in advance