Do Good Undergravel Filters Exist?

[Plecc]

Hi all,
A buddy of mine is setting up a large aggressive tank with a pair of external canisters, he likes the idea of running undergravel filters connected to the intakes of the canister filters to reduce maintenance a bit and add some extra biological media.
 
But he also wants to have a large amount of slate to create a rocky cichlid style tank.
 
I'm fairly convinced that most of the undergravel filters available are fairly feeble and would get crushed by the heavy rock work,
Does anyone know of a company making really tough undergravel filter plates?

 

[TwoTankAmin]

Tell your buddy the canister would only be for mechanical filtration. A properly set up UGF or RUGF (the better choice) is still the single best bio-filter in the hobby. As a result there would be little or no bacteria in the filter.
 
The plates may be stronger than you realize especially with the needed 3 inches of medium sized gravel on top of them.

 

[bucks]

Cheers mate thought id sign up and see what the crack is.

Tell your buddy the canister would only be for mechanical filtration. A properly set up UGF or RUGF (the better choice) is still the single best bio-filter in the hobby. As a result there would be little or no bacteria in the filter.
 

This is what i've been led to believe and want to try a few things out, your not suggesting to do away with the canister filters altogether though?

 

[TwoTankAmin]

No, I was merely pointing out that the canister should not be loaded with much if any bio-media, it should be used to take mechancal wastes out of they system because and undergravel filter will not do this. The canister would also be where you would put any chemical media you might need to use. If you need to use carbon to pull meds, or crushed coral to raise GH/KH etc.
 
When I ran my RUGF I used a powerhead with a sponged intake to power rugf and then an AquaClear filter to help with the mech and chemical.

 

[Plecc]

Thanks for the feedback,
Hi Matt!
 
I assume RUGF stands for "reverse undergravel filter" is that correct?
 
I think Bucks is more likely to want about 1-1.5" of gravel, 3" is a bit overkill, so the weight won't be very well distributed by the thinner layer of gravel.
It appears most manufacturers say not to place rocks or ornaments on top of the filter plates, but i'm not sure if this is because they can't support the weight or the manufacturers are trying to stop customers from creating dead spots across the UGF.
 
I think If you put some good biological media in your top canister tray and fill the rest with 3-stage foam then your onto a winner!

 

[TwoTankAmin]

2-3 inches of gravel are what makes undergravel work. I used three and a medium sized gravel on mine. I would not go with less than 2 inches nor more than 3. The gravel size is important as well. One wants to have good flow through and the smaller the gravel, the lees space there is between pieces. This is why one cannot use sand.
 
Rocks etc can slow flow. You never want to place these directly on top of a plate but on top of the gavel over the plate. Deeper gravel gives the water more paths out when blocked by decor. Also the weight issue can come into play. So it is both reasons for not placing stuff on the plate.
 
I still suggest a powerhead and hang on filter over a canister for a two reasons- cheaper to buy and much easier to clean. But you can still use a canister if you already hove one. Just bear in mind that undergravel filters work best with a slower flow rate.