There is already a thread, which is where i got the instructions.

this is what i used.

the material needed:
1 - 3 foot piece of 3 inch black ABS (cheaper than PVC)
2 - 3 inch cap
1 - 100 foot 1/4 inch black airline ( i used a the more rigid type)
2 - 1/4 inch quick connect union
1 - 1/4 inch shut off valve (U/G Sprinkler Drip controler) *works better

material for growing bacteria - (bio balls and ceramic rings)

electrician tape
pvc glue
teflon tape.


http://www.canreef.com/vbulletin/showthread.php?t=29797