Under Gravel Filter

[Miss Wiggle]

well firstly you can move the tank out from the wall a little (assuming obviously you have space to do so), again just a little bit of pre-planning so get a large bucket big enough to hold all your fish for a couple of hours, fill it up with tank water, catch the fish and pop them in, put the heater in and switch that on so the water stays at temp and cover it over. then drain the tank so there's just an inch or two of water in there, by this time it'll be light enough to manhandle away from the wall a bit, fill it back up with water, transfer the heater back to the tank and when it's up to temp pop the fishies back in.

so don't think that moving the tank is not an option at all, it may very well be possible so if you can find yourself a nice HOB filter then go for it! It will definately make a difference to the filtration capacity long term and if you did it shortly may just be enough to give the bacteria a last little push to get it cycled.

 

[Schmill]

Another alternative would be to use something like my Interpet PF2 intank power filter.
No tank moving required.
No filter hanging over the back.
Seems to give good filtering, both physically and bacterial

 

[waterdrop]

If your DH is like me, he would probably hmm and haa and make up a number when you ask him what depth of gravel this particular UG needs to operate probably (cause 95% chance he's never had a thought about it!) As long as you're going to end up having a fuss about spending even more money on the tank, why not at least give a passing thought to going all the way and getting a decent cannister for it. I'm running a cannister on our 28g, a gallon smaller than your 29. I'm not sure what cost you could find a TetraTec EX700 for, but their supposed to be pretty inexpensive and that would be about the right size for a 29g I believe. The cannister would need only room for the hoses to go up behind the tank and of course cannisters have by far the most media volume of the filter types being discussed.

On the other hand, if you can move it out per MW's plan, there are AquaClear HOB models that get pretty large and probably wouldn't have that much less media volume than a cannister (remember, you don't want to go by the manufacturer's numbers for "max size tank" as they will exaggerate. Instead you must find their "flow rate" number and calculate 5x turnover for your tank.) Regardless of whether you go with used or new for the filter, you will have to study web pages to find the correct flow rate for the intended model of filter. One of the good things about AquaClear is that you have more flexibility to go with different types of media, whereas many other HOBs try to lock you into proprietary "cartridges", attempting to get you go buy replacements all the time.

~~waterdrop~~

 

[Miss Wiggle]

the tetratec x700 is about £50 in the UK if that's any help. i just got one the other day as a second filter on my tank (always like to run two if possible) and i'm v impressed with it so far, dead easy to set up and the most effective self-prime i've ever seen on a cannister filter. obviously it's only been running 2 days or so therefore i can't really say much about it's long term use!

 

[Gilli]

I have an undergravel filter in my tank and the instructions were to have the gravel depth at 2 inches.

 

[OldMan47]

An RUGF is a reverse flow UGF. Instead of pulling water up through the risers, you pump water down them and let it filter upwards through the gravel. By getting flow going in that direction, you never end up with stuff under the filter plate that you can't reach and you don't end up with wastes caking in the gravel. In that direction they become pretty much a biofilter only. The power head that you use to power a RUGF needs some sort of mechanical filter on it to keep the water clean. I have even read of people using the flow coming back from a canister filter as the water that goes down the RUGF riser. Like I said, I think this is the type I have seen Colin_T write about but I have never tried one that way.

 

[OhMyFish]

Thanks for all the information.

Although I'm running only an under gravel filter in a 29-gallon tank, I'm not convinced it's the best or even great. I've learned that it takes a long time to filter--days or even a week or two! I've learned that there's a mess under the gravel which I would prefer not to be there. However, I won't let what I can't see disturb me. I've also learned that I have been unable to find replacement carbon. Well, I can find the carbon but the sections that hold the carbon won't come apart to be filled and I can't find pre-filled sections to fit what I have.

I do wish I had not begun this tank with an under gravel filter. The reverse under gravel filter sounds terrific, though! I'm still looking for an appropriate sale for another type of filter but the canister is not in the budget this year.

 

[hazeredmist]

I have been running an undergravel filter with my fish for over a year now, and I strongly recommend it despite the various controversies you hear. So long as you keep up with gravel cleaning, you will have an immensly clean tank with no unsightly 'dirty gravel' (I recommend gravel cleaning alongside water changes at least once a fortnight to achieve this) and happy, healthy fish. Like any filter system though, if you mis-use it or do not keep up with maintennance, you will have poor results.

In addition, I wouldn't recommend adding carbon to an undergravel filter, which in my opinion is unnecessary and will cause problems if you do not change it regularly.

 

[waterdrop]

In the hands of the experienced, all reasonable filtration methods can be coaxed into adequate performance. Once the beneficial bacteria finally build up in the media of an undergravel filter (the gravel itself) they will be quite tenacious and will withstand all the gravel cleaning and under-grid cleaning you can throw at them, so the trick is to figure out a method and frequency that works to keep the loose "mulm" clear from under that grid and of course to keep the gravel clean via normal gravel cleaning.

As OhMyFish is already an expert in, the awful part is getting an undergravel system up to speed to begin with! Thank goodness that appears to have been accomplished!

Really nice to hear from ya, OMF!

~~waterdrop~~