Hi . Iam setting up a new 112 litre tank and was offered a 600lph external filter is this adequate for my tank or do I need more ?
Should be adequate enough, assuming that it is a canister filter. In most cases, when choosing a canister filter, shoot for a 5-6x times turnover rate of the volume of the tank. When choosing a HOB style of filter, shoot for a 8-10x times turnover rate.