# Pros/Cons of under gravel filter?



## Limeylemon (May 6, 2011)

I have a 30g 30" long aquarium, it has alot of live plants, and a thick layer of gravel.
I am using the elite stingray 15 filter, but i am constantly syphoning so much 'yuck' out of the gravel i'm wondering if i would benefit with an under gravel filter.
I don't over feed, my corys and 'big george' the pleco sort that out.
Wondering if anyone has experience with this setup, pros and cons.
I know 1 con... messing about installing it, but would it help?


----------



## Byron (Mar 7, 2009)

There are pro's and con's to undergravel (UG) filtration. I used it for many years, but now I would not even consider it for a planted tank.

Every planted tank author writes that it can "work" to some extent if it is already in the tank and one wants to switch to a planted tank; but if starting from scratch, it is not the preferred filtration because it has negatives. The main reason is that it pulls the water down through the substrate too quickly. There is (or should be) a natural water movement down through the substrate and back up through the substrate; this is caused by thermal currents and involves all the various bacteria. You can read details here:
http://www.tropicalfishkeeping.com/freshwater-articles/bacteria-freshwater-aquarium-74891/
Reverse flow UG filtration is worse in this respect (in planted tanks). I would not bother with UG filters in planted tanks.

Byron.


----------

