Thanks all, I have a 75 litre tank set up, been set up and doing well for months, started having a couple of problems recently, thats how i found this forum. I think i've kind of done things the wrong way round and tried to self teach myself, been lucky so far with the tank so now i'm trying to learn what i've done right/wrong etc! I don't have a picture at the moment but i'll try and get one put up soon. Thanks for all your friendliness and advice so far x