If you are useing an airstone, then no. If you have a powerhead it may be OK. Or just ditch the UGF and go with another type of filtration.

My suggestion would just be to scrap the whole undergravel and go with a nice hang-on filter instead. Undergravel was all the rage for a few years, but then we all discovered that they are inherently dirty, impossible to clean, and rather ineffective at doing much except pulling goo down into the gravel.

But generally, I'd have to say that you can't really remove the lift tubes and continue to have the filter work at its normal effectivness. With one powered by airstones, you will completely destroy the suctioning effect of the filter. And with anything else, you'll at the very least disrupt the water circulation in the tank. =)

On the whole, however, UGF are basically useless. Without making the jump to a serious, heavy-duty wet/dry or sump filter (which is probably not necessary anyway if this is just a simple tank)... try a hang-on-tank filter like the BioWheel. For simple tanks, I've always had a great deal of luck with these sort of filters. Not only do they effectively remove soilds (mechanical filtration), they have charcoal in the cartridges to improve water quality by removing toxins (chemical filtration) and the BioWheel models have the wheel-o-bacteria (the namesake of the BioWheel) to assist in biological filtration.

I gave up the undergravel ten years ago and never looked back! =)

hmmmmm... thanks you all for the info. The problem is, my tank is kinda small, so there are very few hang-on filters that fit my tank. But thanks anyway!

What size tank do you have?

There are hang on filters for as small as 1/2 gallon tanks that would surely work on yours. I have a 10 gallon and have a walmart hang on back filter that has been doing great for 3 years. Check them out.

You could try the palm filter by red sea for HOB type, Or an internal cartridge kind or even a small corner tank type so you can reuse your airpump. I would go with the small HOB type. Also depending on size you can get a canopy/light/filter combo Ivve heard works well.

Please do not listen to jadewolf, because he is lying about the undergravel filter. I use them and its highly recommended. Its very easy to care for, very clean, and effective. I do not want to type everything about it, but I suggest you to look up the information.

As for you jadewolf, I highly suggest that you get into the habit of monthly gravel suctioning when making water changes!!! You think the undergravel filter make the gravels dirty? Think again!!!

The people who most recommend UGs, are those who manufacture and sell them.

It's not that UGs make the gravel dirty; they don't.

The real problem is that UGs give the appearance of clean gravel while they trap dirt under the plates, where it sits, waiting to trigger a bacterial explosion.

At best, UGs should be used only in well (live) planted tanks and even then, water changes should made by siphoning out the water through the uplift tubes.

One way to use a UG with some safety, is to add clean, conditioned water to the tank as the siphon is pulling the dirt from below the plate.

If you are cleaning a 10 gallon tank, you would siphon 5 gal. out through the UG uplift tube, then top the tank off again and repeat, until no more visible debris is in the dirty water.

But the best way to keep any tank clean is still water changes and the smaller the tank, the more frequently it needs it.