Undergravel filters good bad?

[Rhys19]

Hello everyone of the TFF I would like to ask a question about UGF's I've read some websites and there are people that say they love them and some say they hate them now my general question is:

Is it really worth it?
Could it be used with my HOB Filter?
would it really help improve filtration?
what good does it really do? it only cleans the gravel right not the actual upper part of the water? and secondly, I would think people with live plants would go against this since 1 it cleans the substrate, and 2 it seems to remove all that fish waste that LP thrives on.

anyways my opinion is: No because the substrate cleaning with my planted tank would remove the nutrients from the substrate.

let me know your guy's opinions on it!

 

[itiwhetu]

I've used under gravel filters for years and love them. The only ones I have used are DIY filters made with PVC pipe and run off an airstone ( See photo below ). What these do is drag the fish waste into the substrate to be used by the plants. This type of filter ensures that the base of your tank is aerobic all the time, as there is a constant flow of water through the substrate. You never have to worry about vacuuming your tank. The filter below is exposed because of a lazy fish keeper, but usually the pipe would be buried in the gravel. I should note that the inside of the pipes get covered in BB and the whole thing becomes a big bio filter.

 

[AbbeysDad]

The under gravel filter is a great Bio filter. But like all filters it requires routine maintenance and has some shortcomings. Because it's gravel, uneaten food, along with plant and fish waste is drawn down under. This is exasperated by too much air flow or powerheads that pull too much water (and waste) through the gravel.
This requires routine gravel vacuuming to remove the waste. If this is not done, the gravel filter can easily become a nitrate factory. I know this firsthand.

The best way to use the under gravel filter is to use it with only a slight flow through the gravel. But as mentioned above, all too often, excess in airflow is used which pulls too much waste deep into the substrate.

I much prefer an undisturbed sand substrate which means that an undergravel filter just can't be used unless you subscribe to Dr. Kevin Novak's plenum method. This would require landscape fabric between the UGF plates and the sand AND only use a slight flow through the substrate.

So the UGF can be a great filter when managed properly. But I'd be careful about the gravel size, only set it up with a slow flow rate, and it must be vacuumed as required.

The UGF may or may not have a negative impact on rooted plants.