I am getting ready to upgrade from my 20g long with HOB filter to a 40g breeder and this time I want to drill the tank and build a sump. I am planning on around 250-300gph flow from the return pump. Would 3/4" plumbing from the overflow allow this or should I plan on using 1"? Also I am thinking of two 1/2" return heads so I can get away without using a powerhead for a cleaner look. Tell me what you think I should change. Any input is valued!