Under gravel filters?

[Sssea]

Waste of time or worth the money for the added filtration?

[Mr. Limpet]

Why not just add another HOB? Easier, safer and if you need a backup on a QT/additional tank, it's ready to go.

UGF's used to be the only filtration you could get, now they're rarely used IMO. The problem I see with them is they don't really take anything out of the tank, they just hold it via vacuum under the gravel (can't use sand with UGF from what I've read), but if your pump fails then all that gunk could become suspended and create all kinds of troubles IMO.

[Sssea]

I was thinking more to get all the goldfish mess out without having to vacuum every 5 minutes, but if they're not much help, I'll just stick with the vac.

Also, I heard you can't use sand with goldies? Pros and cons?

[Mr. Limpet]

Originally Posted by Sssea

I was thinking more to get all the goldfish mess out without having to vacuum every 5 minutes, but if they're not much help, I'll just stick with the vac.

Also, I heard you can't use sand with goldies? Pros and cons?

I have Black Moor's and I totally get where you're coming from lol. I filter for almost triple my tank size and that seems to be a good balance. I like the aqua clear filters (AC50 on my goldie DT) and they do a superb job of cleaning up after the trio.

I use PFS in all my tanks and love it. I plan to put it in my goldfish tank too, once I get everyone else settled. I'd suggest you do research and check what sand you put in, since goldies are always booking and will most likely ingest some sand grains, you want a smooth round grain that will pass easily.

[Sssea]

What's PFS?

[AquaOne]

Yes, what is PFS ? (something, something, sand I guess).
UGF's are okay until the pump stops, also difficult to clean up without a near total strip-down ! Sand on a UGF would surely just get pulled through so that's not good either. No reason why goldfish shouldn't have sand (or that PFS stuff !)

[Mr. Limpet]

PFS=Pool Filter Sand .

[Sssea]

Originally Posted by AquaOne

Yes, what is PFS ? (something, something, sand I guess).

Totally made me giggle.

Thanks for all the info, guys. I hear sands a little easier for clean up because all the business sits on top?
I know almost nothing about gravel/sand except that my fish are little poo machines and I'd like to keep the bottom their tank much cleaner.