Craig89
Fishaholic
Well it would have been a good idea but the gravel went a long time ago. Just done first water test and everything is fine and all look happy 
ow dear. Better look next time i guess.Well I got a bit cautious about putting bare cement in the tank so went and got some G4 concrete pond seal. As I was applying it, it penetrated the cement and melted the polystyrenenot to worry tho I will be attempting it again