ok so my nitrates are out of control and i want to adda fuge to my 50 gallon acrylic with a wet dry built in the back. I know how i can do it, i can drill for a standpipe in the back where the water level is supposed to be. would i need to drain the whole thing of water or just get the water level below where i need to drill it? also, since i have absolutely know experience with an overflow system or drilling for fittings, where do i get what i need to do this??? alsois there a special type of bit i should use?