Can you use a sponge filter in a saltwater aquarium, not a simple sponge filter but one who can hold media in it . I wanna setup a 30g. I already have a 72inch light for two other tank besides it, and a well established tank to help kick start it. I’m only planning to add a couple fish around 5 Molly that we’re bringing in my main tank and maybe a six line wrasse and or a goby and pistols shrimp duo. And some easy care corals zoas and Kenya. So it’s a spring filter with a medium basket built into it good okay for salter or do I need a hanging in the back?

