my first saltwater aquarium

Question
what is the smallest tank you  can have for marine if i have a undergravel filter do i need a protien skimmer

Answer
under gravel filters are incredibly outdated and useless, live rock is a good enough filter on its ownalso the bigger the tank the easyer it is to keep your water perameters stable.

small tanks are pretty hard to keep, not really recomended for a beginer, but i would say 25-30 UK gals is ok for a pair of clown fish (nothing else)