This is a DIY sump filtration system for freshwater as well as marine aquariums,this type of filter can handle large amounts of bio loads,can be easily built by a hobbyist with only a hand full of tools.
Step 1: materials required
1.a box of any kind preferably with a lid[dimensions 8''x4''x5''(lxbxh)]
2.PVC pipe of 1 dia
3.PVC pipe of .5 dia
3.a power head of displacement capacity -300lph
4.filter media.- bio balls,sponge
5.glue of some kind.etc