UGF is doing great!

[mvigor]

I thought I would post my positive experience with a traditional flow undergravel filter. I have UGF in both of my 20H goldfish tanks, driven by a W-Mart powerhead. The gravel is between 1.5 and 2 inches deep. I also have a "30 gallon" HOB filter on each of these tanks.

Current popular opinion seems to be that a person should either completely avoid UGF or use reverse-flow. My experience says that they work for me.

Yesterday I moved the tank to my wife's classroom and I got a very nice look from the bottom under the UGF plates. It was completely clean under there!

The tank has been running for probably 18 months now, stocked with a fancy tailed goldfish that has grown from 2 inches to at least 5 (in body length) and for the last couple months also with two messy plant eating apple snails.

I'll report back again on UGF when I move the tank home in 9 months. It surprised even me that there was literally NO MESS under the filter plates.

 

[Reefmonkey]

I remember in the 80s when conventional wisdom shifted to UGF only being effective if you have a powerhead. After I abandoned them entirely (I found my HOB filters were doing all the work) I didn't keep up with the discussion, so interesting to hear that now it's reverse flow is the only way to use the things.

Actually, if I remember, there should be some detritus under the plates if it is working properly.

 

[mvigor]

As a bio-filter I have to say that it's probably working. I can release colored tank water near the gravel and watch it get sucked down and then come up the tube, drawn by the powerhead.

 

[hashbaz]

I have heard that UGFs are Nitrate factories and my 29 with a UGF had high nitrates so I ripped out the UGF. The nitrates stayed the same - the only difference was my water had a lot more "floaties" after removing the UGF.

I don't know why everyone bad-mouths the UGF so much. My only complaint is that the up-tubes look ugly.

 

[mvigor]

Here is a thread on another site where we discuss this same topic at greater length.

 

[7Enigma]

The main problems as mentioned are that they do tend to cause a buildup of decaying matter that make your tank ripe for nitrAtes.

But the honest reason why I think most moved away from UGF and why new people to the hobby have avoided them is the work required to keep them in top shape. With a UGF you should at least once a year tear down and clean under the substrate to limit the amount of nitrAte produced. Moving substrate/plants/fish/etc. is not a fun process, and the UGF's can get VERY nasty underneath the substrate.

HOB filters are much easier to maintain and clean. My AC HOB filter takes about 3 minutes to rinse the pads when the flow lessens, and its back to >90% flow.

So I don't think its a matter of UGF's being bad, I think its the simple fact that HOB's are so much easier to maintain.

 

[Reefmonkey]

Interesting that they are still around in the hobby, and old technology revitalized with powerheads and reverse flow. I'm only 30 and I still remember as a kid they were the standard, and I never thought they did much with the little airstones, read that powerheads were just starting to be the way to go, but I went with HOB. I remember at that time hearing from people who were telling me how terrible it was for me not to have UGF, that my gravel would get anaerobic, all my fish would die, there would be no way I could keep my tank going without one. Of course, I guess there once was a time when the conventional wisdom was you couldn't keep an aquarium without live plants. Since I have mostly kept brackish tanks and rift valley tanks, I haven't used live plants except for a paludarium a while back, until my new pond this summer.

 

[mvigor]

The main problems as mentioned are that they do tend to cause a buildup of decaying matter that make your tank ripe for nitrAtes. With a UGF you should at least once a year tear down and clean under the substrate to limit the amount of nitrAte produced.

The tank has been running for 18 months now, stocked with a fancy tailed goldfish that has grown from 2 inches to at least 5 (in body length) and for the last couple months also with two messy plant eating apple snails. There was literally NO MESS under the filter plates.