My Review Of The Infamous Under Gravel Filter

[Ilya]

Even I don't have one, I've come to the conclusion that I should have used one over the wet/dry trickle filter. It's probably better then most (probably not better than a canister filter, I don't know) filters. The reason being that the substrate acts as the filter media. Now, what's so good about it is that it's one HUGE filter media. And because it's so big, it can hold a lot of (good) bacteria. And in return, a safer tank. Cleaning is easy, all you do is give it a good gravel vac. The only downside to the UG filter is that it may clog up every once in a while. But with good maintenance, clogging won't happen.

Q. If you vacuum the gravel, won't it suck up the bacteria?
A. Yes and no. If you clean all of the crud from the surface layer, the bacteria on the bottom of the gravel won't be bothered. And there is a lot of bacteria .

Comments and critiques please 8).

 

[kribensis12]

I think it is a good, short but sweet view of a UGF. I have never really like them, and have had instanses where my fish, and babies will swim into the pipe thing's where the air come's out, then, swim under the filter, get caught and die a slow painful death, as i cant get them out w.o getting rid of the gravel, adn possiby destroying the fish during the process.

 

[Mr._Fishy]

I think that the UGF is very underrated. It's biological filtration is usually the best besides a sponge filter. IMO, they are better than canisters. Great mini review and I agree strongly with you.

Ryan

 

[shroob]

I still think that the trickle filter is the king of filters, though I can accept other filters have their benefits.

 

[eschaton]

They are kind of awful if you need to add carbon for some reason though, aren't they?

Also, they don't work very well with sand or a planted tank in general.

 

[OohFeeshy]

No fish prefer gravel over sand.

End of, IMO.

 

[Mikaila31]

I think they are awful, if used the way they are suppose to be used. Here is a pic for those unfamiliar with this kind of filter, they are kinda old. They can be used with airstones or power heads. The grates go on the very bottom of the tank and the gravel sits on top. You can gravel vac with these filter, it is no different then cleaning your filter media. The problem is that debris can make it's way down through the grates, this builds up over time and causes water problems. So you do have to clean under the grates every now and then, which is a real pain.

That said they are very useful for other purposes , best used in fry or quarantine tanks though.

The most common:UGF powerhead+ UGF pipe + filter floss= sponge filter

Not so common: UGF grate+ soft door screen+ aquarium silicon= tank divider made to your liking

 

[Biulu]

I am very happy with my UGF, even in a planted tank. Actually, my plants are 'eating' all the waste of the plants, food etc. However, I would not use this type of filter in a big tank or you need to add on a powerhead. I think though it is a great filter if you are using gravel as a substrate anyway.

 

[hyak2]

I am a big fan of air driven undergravels - you can even get away with it in a planted set up with plants such as hornwort,javamoss & fern, hygrophilias and various ferns and floating plants. I also put amazon swords in and they grow extremely well if planted in a big yogurt pot with holes punched in, filled 3/4 with irish moss peat, and then topped off with gravel.

In a nutshell:

*highly efficient biological and mechanical filtration
*very gentle water movement - ideal for many fish species
*copes with ammonia surges better than most other types of filter
*easy to look after and unobtrusive
*cheap
*easily clean under the plates by setting up a syphon tube in one uplift and using another placed in the opposite uplift, blow down this one to dislodge debris which is vaccummed away by the syphoning tube

the only instances where i would use different kinds of filter to this are when housing especially large messy fish or those which dig around alot in the gravel and cause easy flow-through places where water flow channels where the gravel is most shallow.......

Alot of people will bash them but when used properly i think undergravels are easily as good as many of the more advanced filters available.

 

[xxBarneyxx]

Personally I wouldnt use an UFG by itself unless it was in a QT or hospital tank (and then I would still most likely use a sponge filter). They do work though. I remeber my parents kept tropical fish for years with just a UFG and the fish did really well.

If I was to use one now though it would be a reverse UFG to aid biological filtration with a canister filter to remove particals from the water. They can be useful for messy fish that produce a lot of waste but i dont rate them as having any mechnical filtration as everything just gets sucked down under the plates eventually where it sits and rots.

The other positive use for them though is if you have a tank where you cant fit an external filter and you dont want to take up space with an internal filter. You only have to have a couple of uplift pipes and maybe a powerhead and these dont take up that much room.

 

[SouthernCross]

I recently tore my tank down (I had a UGF and HOB) and after seeing the muck under the plates after only 8 months I tossed the UGF. I was ont looking forward to having to do that kind of maintenance again. And I gravel vacced out 4-5 buckets of water every week, its not like I neglected my vaccing.

I took pictures, just haven't got around to posting them yet.

 

[SJ2K]

Only UGF id use would be a reverse UGF along side a powerful internal to catch the results.

 

[grimmy]

i love ugfs they have supior biological filtration. in my opion a power filter such as the pennplax bio falls combined with lees ugfs are the best combination there is

 

[Tolak]

I recently tore my tank down (I had a UGF and HOB) and after seeing the muck under the plates after only 8 months I tossed the UGF. I was ont looking forward to having to do that kind of maintenance again. And I gravel vacced out 4-5 buckets of water every week, its not like I neglected my vaccing.

I took pictures, just haven't got around to posting them yet.

Substrate in general is a filth collector, running ugf makes it even more so. All but 4 of my tanks have no substrate because of this, if you want a clean tank pull the substrate. I gave away the last of my ugf plates long ago, I have no use for them.

If you enjoy tearing down tanks on a regular basis by all means run them, they are excellent bio filters, at the expense of having some hidden filth that is a serious job to remove. Im surprised that nobody has added a cappable access to the filter plates at the front of the plates to hook up a siphon & remove a good portion of this filth. The furthest point from the riser tubes is where the majority of gunk seems to build up.

The only serious setups I have seen running ugf are a couple of local shops that have been set up & running for decades, they are old timers, and not about to spent the time & money upgrading.

 

[Bignose]

In almost every case a hang-on-back filter is better, especially one with a bio-wheel. The best thing about having the bio-wheel is that you know exactly where all your good bacteria are cultured, so so long as you take care of that wheel, you don't have to worry about re-cycling the tank.

There was a time that the undergravel filters were the best technology out there, but today that is just not true. Here are some of the drawbacks: the gravel bed, since water has to flow through the bed to be filtered, may develop channels, also known as ratholes, through the bed. This is bad since if the water is not running into the gravel too often, it is effectively getting not filtered. And that will happen since the water will take the path of least resistance, which is the rathole. Next, since the bacteria are under water, the water has to be well-oxygenated... the good bacteria need oxygen to work. With a bio-wheel, the bacteria are exposed right to the air, which gives them at least 1000 times more oxygen to do their work with. Another thing I like about the biowheel filters is that you can immediately see if it is working correctly, that you can see if the flow rate of water is fast enough, you can see how often the wheel is spinning. And, again to fix this, you just take the wheel off, float it in the tank, and then clean out the filter itself. You know the bacteria are safe on the wheel, and you can clean that filter and pump and the filter pads and anything in the filter as much as you want without worry about a cycle. Comparatively, since with an undergravel filter the entire bed is the filter, you actually have a limit on how much you can clean the tank. Clean too much, and you may cause a mini-cycle. With the bio-wheel, so long as you match the pH, hardness, and temp of the new water with the tank water, you can actually do as large a water change and cleaning that you want. This could be good if an emergency arises.

Ultimately, you can never use sand or soil substrates with an undergravel filter, and very few plants do well -- they don't appreciate the currents on the roots. There are just better, easier technology for use today.