Upgrade to Wet-dry filter?
I have a 30 gallon tank with a hang on back filter but im thinking of upgrading to a wet-dry filter under my tank. I have a fish reef tank established but my nitrates a hair high and I'm having trouble keeping new corals and anemone alive. Any advice on what to upgrade to or what to stay away from. I'm new to this type of filter so i don't know much about it. Thanks for any advice.