Sub-Gravel Filters

[KaiserSousay]

Thanks for the info thus far! If it is good filtration method why did cansiters and other filters come out?

Same reason you don`t have to clean out the stall of your ride to work

 

[crazy clowntang]

I think a lot of people just don't use them because of the new "technology" i.e. canisters, sumps, etc. I have had UGF before and they work fine. Most people nowadays use sand and not gravel as substrate so a UGF makes no sense to have. If you use small to medium gravel UGF work great. Also people with planted tanks don't use them. I will say that water quality and clarity with UGF seems to be good all the time.

 

[abarilot]

Thanks for all the informative answers!