undergravel filter

[dave76]

On these forums I have always read people saying that UGF were the worst, but I have never seen anyone say why? Can someone elaborate on this for me?

[thom336]

I have never had a problem with UG's, but they are a bit out dated, and are not as good as newer filter models and designs, such as internal and external power filters. In preference I would go for one of the newer models as they are better, but I still have faith in UG's. They are certainly not the worst - but there are better out there.

Thom.

[ChilDawg]

Part of the problem is the fact that the flow can often cause particulate matter to be gathered under the gravel. If people clean the UGFs every so often, that would be less of a problem, but it is a pain to do so (you must remove the gravel and then the filter), and larger fish can render these obsolete quickly because of their large volume of waste.

The success of the UGF relies upon particles being forced through gravel, so any uncovered gravel causes a pool of debris to form, which is not exactly the point of the filtration.

As Thom said, it is outdated, and there are some dire consequences if it is not properly maintained.

[dave76]

I bought a aquarium about a year and a half ago, it was a full setup, 55 gal with emporer 400( I assume that is what this filter is because it looks like one and has two biowheels) and a undergravel filter with two powerheads.

Are there certain kinds of fish you should avoid using a UG with? Or will this combination suit most freshwater tropical fish?

[thom336]

Generally avoid large, messy fish, as they will clog it all up very quickly.

[dave76]

I just got a Green Terror two days ago. He is still a Juvenile and about two inches long. Should I wait till he gets bigger or should I just disconnect it now?

[ChilDawg]

May as well disconnect it now...the fish is going to overwhelm the system in no time, and he might start digging before that point is reached.

[JSchmidt]

Most cichlids are inveterate diggers. As they dig, the expose the UGF plates, allowing water to pass thru more freely where there is little or no gravel. This renders much of the UGF useless.

Besides diggers, any fish that produce lots of waste may be poor candidates for UFGs.

A superior form of UGF is the reverse flow UGF (RUGF). This version uses powerhead to push water down thru the UGF tubes where it rises UP thru the gravel. This helps avoid the problem of fish waste being pulled into gravel and beneath the plates. Also, the powerhead generally are outfitted with prefilters to help avoid pushing crud under the plates. RUGFs still suffer from bypass when used with digging fish.

RTR's over-engineered UGF (http://www.tomgriffin.com/aquamag/rtrrfug.html) is a good solution to all the problems with UGF.

UGFs (& RUGFs) are economical filters, but they must be maintained. I run a couple RUGFs and they function well, but I prefer other, more easily maintained filters.

HTH,
Jim

[Slappy*McFish]

^ Everything he just said...You took the words right out of my mouth JSchmidt;)

[dave76]

would the emp400 be suffiecient or should I seek other methods of filtration?

55 gal
1 pictus cat
1 juvenile green terror
1 sailfin mollie (move pending)
1 zebra striped danio (survivor)



"As Thom said, it is outdated, and there are some dire consequences if it is not properly maintained."

please elaborate


thanks again

[ChilDawg]

This thread might help: http://www.aquariacentral.com/forums/showthread.php?s=&threadid=10814

[CHINABOY1021]

i havent read the prevoius posts, but i'll make myself short.

UGF, dont remove dibris, it jsut help it stay on or in the gravel where it can not be seen.

other filters remove the debris into the filtering chamber which can be cleaned easily.

UFG, looks bad plus UFG + air pump needed = probably same price as some kind of AC HOT filter. i recommend aquaclear to anyone, unless the filter can not possibily handle the bioload. thanks!

[RTR]

No aquarium filter removes debris, they all sequester it for manual removal by the hobbyist. Since I vacuum all my unplanted tanks routinely in any case, that is not an issue for me. And I have not used an air pump in decades other than on fry tanks. Even OE-RFUG would be far cheaper than the external canisters I use routinely, but cost is not the issue or reason for selection. I use them in part because they do keep the gravel cleaner than I can myself with mesy fish such as puffers.

But I must admit that all my UGs are OE-RFUG, and most are in tanks where I want higher pH/GH/KH than my tap, so use OE-RFUG w/aragonite substrates to support that requirement.