Just food for thought....I had a 120g marine tank with a 1200gph pump in the wet dry. It caused too much flow for my puffer and the living rock. When I throttled it down to reallistic flow, it over heated the water and nearly killed off the whole tank. the back pressure caused an extra load on the pump which caused extra work on the water. Sorry for the thermodynamics lingo...in a nut shell the work done on the water translates into heat...which is carried into the fish tank. If you are in an area far enough north where you always have to run your heaters, this may not be a problem. Where I live, heaters are a winter time thing...and winter only lasts for about two weeks here...
To size your pump, use your tank volume and your desired flow. Ten turnovers is way too many per hour. The total number of turnovers of course will be limited by your other equiptment such as bulkheads or dirty filter media. If you are adding a wet dry to your system, you only want the water to trickel over your media. If you are adding a wet sump with filter floss, gravel, etc., you can have a higher flow rate.
Wet dry filters allow the removal of organics through biological break down by employing aerobic bacteria. Some anaerobic bacteria also live in the media and will remove those dreaded nitrates. I don't remember the rule of thumb for marine tanks using wet dry filters, but fresh water tanks using them are greatly enhanced as well. A wet dry on a fresh water tank is really an over kill, but in my book...the more the merrier. A wet dry is beyond the equivalent of lining the entire rim of your tank with bio wheels. You can over stock your tank to the point of beyond rediculous. I am currently finishing a low budget wet dry to handle the messy load of pacus or piranhas. Total cost to date...$8.