i just bought a 180gal today
with 2 overflows and 4 holes in the bottom but i am new to this type of tank im am use 2 non drilled tanks so i would love help ideas the whole sha-bang
im open to all ideas and input



SEE I AM A GREEN HORN TO BULK HEADS AND STAND PIPES AND WHAT HAVE YOU I HAVE JUST BEEN USING A CAN OR HOB OR AIR PUMPNate77;1015047; said:2 of the holes are for your overflows which are more then likely 1" for bulk heads and stand pipes.the other 2 which are more then likely 3/4" for your return lines.Its easy to setup up if you don't put much thought into it.
Did Ming REALLY just recomend drs foster and smithM|L;1015221; said:go to google and search for wet-dry filters.
basically, the holes already drilled in your tank is for the purpose of transfering the water to an outside filter, and in the case of an "wet-dry filtration system", the outside filter would be the "sump".
the sump can be home-made out of another smaller fish tank or a plastic bin (or whatever holds water), and that's where you put all your various filter media that performs the mechanical, biological and chemical filtration. then the water gets pumped back into the main tank.
again, search for "wet-dry filter" and you'll get a better idea of how it works. if you have the money, go to drsfosterandsmith.com and buy the entire wet-dry filter setup and you'll get the hang of it.