Anyone have undergravel filters? My new 18 gallon has an undergravel filter and I'd like to know if I have to take out the tray. Yikes I never have yet and I am terrified someone will tell me I shoulda What am I going to find under there ( tank's been running about 2 months...) There's a side bio wheel filter too.

Have got undergravel filter in tropical tank.No you don't have to take it out,turn undergravel filter off.Just remove all your fish.Reduce the water then use a gravel cleaner.thats it done.You only need to remove plates once a year.However I was told by someone on here that undergravels are not recommended for use with goldfish due to ammount of waste they produce.

Thanks Blue . Well I have 2 small goldfish in there and I know they are not the best filters so I have the biowheel and the overhead filter too. I do the gravel vac (with the fish in) fairly often, glad to hear I didn't have to lift that tray .

Too true Blue The reason I dislike undergravel filters is that they only remove some of the waste while the rest gets trapped around and under the plate. If you remove the plate at all - I would also remove your fish and do a massive waterchange - then leave the tank empty for a while. This is incase any harmful gases get releasted and need to be gased off...

There's nothing quite like a good gravel vacuum to keep your gravel clean and your fish healthy

Jen, we posted same time...thanks for the reply . If I remove the plate and leave the tank empty- how long would my cycle stay intact with no fish in? There's a good smell in this tank and good water parems at the moment but if nitrates increase (presently 5) I am going to have to remove the plate right?

As it's only been in there 2 months - it shouldn't be too messy. You would only need to keep the fish out for a couple of hours and then only if the UGF has been in the tank for some time. In your case, i don't think it's necessary. Perhaps in the future, you could look into upgrading to another biowheel perhaps? Together with your existing biowheel, they will keep your tank clean and cycled removing the need for an undergravel filter

I could do that but its a small tank so I don't want to crowd it. I could get a biowheel that goes in the overhead box I guess. Thanks

i was told that the underground filter helps break down the waste into nitrate and nitrite or something creating a nitrogen cycle. i have the undergravel thing, but just have a power head so it could suck water from under cycling the water under the tank.

it seems to be working for me! plants are growing like crazy. the fish is nice and happy!

Well, I have to say I thought they were ok until I got my current fish who were adopted from someone else. They were in a 10 gallon with a ugf and MAN when I finally pulled it out because I was having problems it was the nastiest thing I have ever seen, EVER. It was hard not to throw up, literally. Granted, this was an overstocked tank, but still I can barely handle not vaccuuming the gravel every three days.

I think what happens is that they work well for awhile, but with messy fish like goldies, eventually it will stop working and all that trapped waste causes the water to turn toxic (isn't that where "old tank syndrome" comes from?) .

I would never have said it until I saw it with my own eyes, but just knowing all that guck was under there, I could never use one again. After only two months it shouldn't be too bad, and I am no expert but I would lose the ugf if you can. *blocks thoughts of pulling out ugf from tank*

Interesting. I'm beginning to feel a nasty premonition coming on .
And....
The other day doing a water change I banged the side of the plate and noticed the wierdest pink lump bubble up from somewhere. It was small and I fished it out and looked more closely and saw it was afood pellet swollen twice its size and cased in a kinda clear jelly (mould). It was a very rotten piece of food...and I am wondering if there is a lot more under there....oh it's such a pain***if this is not going to work out because I have no other tank these 2 pearls can go right now, my other 2 tanks are full .

That's why I really dislike them. Food will rot and become encased in a nasty mould which adds to the amount of work your filter has to do. But the waste will sit there getting all manky...

I wouldn't panic though - is there any way you can place your fish in one of your other tanks while you remove the plate? Just as a quick visit - which shouldn't do any damage to your other fish.... Also, how many gallons does your other filter turn over per hour?

You might do well with a hang on filter to replace it - there's no strong return and it helps with surface agitation. Plus they're easy to maintain..

That really made me laugh!

Yes, I'm thinking on doing that. Everyones healthy right now so no harm in a visit but I don't want o crash the cycle in the undergravel one..

Filters- hard to explain as they are Japanese makes. The 18 gallon tank looks like this

Sorry- a bit hard to see but the left side filter tube goes up to the hood wherein there is a filter with plenty of media in and then the water comes out the right side where I also have a small biowheel corner filter you can see far right (suisaku space power by name -cant read the rest...)

This precedure then would have be a kind of once every few months thing..dreading what I'll find...

Found a product you may be interested in using if you do decide to use the undergravel.Hope you don't tho.
Its called Nutrafin Waste Control.Its an organic product for fresh and saltwater aquariums.It helps remove algae from gravel,filters and aquarium surfaces.So its useful if you don't have some form of algae eater.
Part that will interest you is it helps prevent blockages in UG filters as it breaks down the waste.
I only buy it tho to control algae in my tank I currently don't have an algae eater in and it does a good job.

Yes I expect I could find something like that here to use but I 'll prob go with a second bio wheel instead. I try not to put anything bottled in my tank -organic or not- that's just the way I do it..maybe silly but...(I even let my water sit for 2 days so I don't have to use Prime or de-chlorinator).

Disaster999 - your tank is tropical right? As Blue said undergravels seem to be more commonly used for salt tanks .

no, i have an over crowded goldfish tank as you could see in my signiture. i always use the gravel vac to clean the gravel and i have a power head that cycles the undergravel water. i never saw or smell any disgusting pink bubbles or anything so gross that would make my puke! i could clearly see the roots of my plants and small piece of gravel under my tank and thats it.

You're clearly doing allright with it then. I thought you had a salt tank because of the red striped fish in your tank pic-looked tropical to me..

haha, thats just a nemo food clip i bought from petsmart to hold cucumbers and lettuce and stuff

relieved to hear that !