filtration

[Pototo]

Is there anybody who can tell me how to set up a home made sump filtration for my 120 gallon fish tank? In my fish tank i have a few coral and anemonies. It seems that the nitrates in the tank are high. Since i dont have a lot of money to spend i would like to create a home made sump. In my tank i have a bioweel filter and a canister. The fish and the coral are doing fine, but the anemonies aren't. Also is there any other way to reduce the nitrate level in the tank? Please help! Thanks.

[SKRIZ]

do a water change.

do you have an overflow in the tank? if not, you can add one, take a rubbermaid container and add a return pump, and you have an easy and cheap sump.