View Full Version : Undergravel Filters and Live Plants

H8Parrotfish 13
11-27-2002, 7:54 PM
I heard that you cannot have live plants in your tank if there is an undergravel filter.



11-27-2002, 8:50 PM
I believe it's not that plants won't grow, their roots will grow into the plate which can stop it from being effective as a filter.

11-28-2002, 9:24 AM
When the roots of plants grow into the plastic under gravel filter, it would be tough on the plant to move it for say- cleaning or

Under Gravel Filters collect crud at the bottom of the tank - with nowhere for it to go until it's time to empty the whole tank for cleaning.. Check into canister and HOB (Hang On Back) filters to make life easier! :)

11-28-2002, 11:11 AM
Actually, you can do it. My 20 gal TV tank has been setup for 2 years. It is heavily planted and has a UGF. Now I set this up before I had a Clue, but it still works fine. Plants do well. Water still appears to flow through the UGF.

I would not do it now, as I have learned a few things. But I aint tearing it down either. "If it aint broke, dont fix it" Right?

11-28-2002, 1:12 PM
Another thing you can consider with a UGF is to have plants that don't root in the substrate. There are lots, like java moss, java fern, bolbitis, anubias, that you can attach to things. If you have the ornaments anyway, why not dress them up with real plants.

11-28-2002, 3:46 PM
My experience was like Shiftaltumlock's, though my UGF plate is in storage now. Unnecessarily complicated, IME. The UGF was meant to encourage a slow percolation of water through the rootzone, not fast enough to blast a lot of oxygen all through the gravel. Hooking up a powerhead ruins an UGF. So does vigorously scouring out areas of your gravel with vacuuming.

The accumulation under the plate is humus, though it's often thought of as "dirt." It can be removed by putting a siphon down the riser tube.

There's more rant along this vein at www.skepticalaquarist.com in the set-up folder, under "Mis-Tech" at the bottom... see if you agree.

11-28-2002, 6:44 PM
You won't have to worry about it if you have "rootless plants such as Cabomba and Anacharis. ;)

11-28-2002, 8:52 PM
I too have a heavily planted tank with a RFUGF. Here's the trick: One third of the tank is RFUGF with a foam pre-filter, the other 2/3 have a plantable substrate under the gravel. Best of both worlds. Also, my DIY CO2 bubbles feed directly into the tube between the pump and the UGF plate. As far as I can tell, I am getting 100% diffusion of my CO2.

11-29-2002, 2:04 AM
Matak, that's a fresh set-up concept for me! What size is the tank? I picture it that your UGF filterplate is a single plate that covers 1/3 of the bottom, covered with regular aquarium gravel? at one end of the tank and then an enriched substrate with a gravel top layer, heavily planted, fills the rest of the tank. Is that right?

Then your bubbled CO2 is carried down under the UGF plate and gets pretty completely dissolved in the unplanted section of gravel. And the rooted plants get the benefit of a low-oxygen zone where iron and phosphate are freed from the substrate?

Am I getting the picture?

11-29-2002, 5:32 AM
Wetman, you are 100% correct. I wish I could get a mind picture from someone else's description as well as you do!

There is also the added benefit of low water turbulence, which I understand that some plants and fishes love and also results in less CO2 exchange at the surface. BTW, my tank is a 30G.

The powerhead I have on my RFUGF is this this one (http://www.hagen.com/canada/english/aquatic/product.cfm?CAT=1&SUBCAT=107&PROD_ID=01001600011001) which provides a low percolating flow for the UGF plate and has a sponge filter that will clean out crud before it enters the UGF plate.

Could I get an honourable mention (http://www.skepticalaquarist.com/) about this fresh concept?

11-30-2002, 9:00 PM

11-30-2002, 11:10 PM
Matek it seems fresh enought to me! (I'm starting to edit the website, long overdue!...)

12-01-2002, 8:57 PM
I guess you bumped it for more opinions? Here is my two cents. You can keep thriving plants with an UGF. As others mentioned, in some cases roots might get tangled in the filter, which can be a pain. This does not always happen. I have kept Swords, Aponogetons, Crypts, Vals and other plants that can create a lot of roots in a tank with an UGF and never ever saw this happen. YMMV. I see good growth in root feeders in that tank. Many plants feed from the water column, and do will care a whit if you and an UGF. Those that are root feeders need a good substrate, but an UGF has no relation to that.

If you are setting up a new tank, there is no point in wasting money on an UGF. The filtration that it offers can be accomplished with better filters, and you will have less worries. If you have an established tank that you want to keep plants in and it would be a serious pain to remove the UGF leave it be and don't worry about it. If you have a powerhead then you can set up a Reverse Flow UGF as was described in posts above, which is a nice approach.

Other factors like CO2, proper ferts, a good substrate (if you are keeping root feeders), and adequate light levels are vastly more important on successfully keeping plants than whether you have an UGF.

H8Parrotfish 13
12-01-2002, 11:47 PM
I have Power Heads on my fUGF but I also bought the Hot Magnum set for my 75 gallon. So do you think I should get rid of the UGF or reduce the flow of my Power heads?