Useless Filter?

[Minni3]

I got an under gravel biological filter the other day (under gravel filter to save space so my betta has more room to himself). The filter is connected to an air pump, thus aerating and filtering the water at the same time (bettas don't need aeration but it's good for the circulation anyway). The thing is...the water from the tank is not actually being pushed up through and pass the beneficial bacteria - it just goes up and then goes back down again due to gravity (argh stupid physics). Even with the air pump on full blast (full blast as in it creates waves and currents) the water can't pass through.

I've used "cycle" to speed up the cycling process but at this rate, i don't think it matters, right? Whats the point of good bacteria if the dirty water can't bloody pass through it??? Help!!

P.S. My tank is 3g - so a bigger and stonger filter (one what actually sucks the water up) is not an option here.

 

[ibbledibble]

with an undergravel filter, the water should not be being PUSHED UP through the gravel, it should be PULLED DOWN through the gravel
it may not be noticeable that its working, but thats one of the good things about an UG filter, limited water turbulence
when the bubbles come out of the airstone they pull the water up with them, and it pushes out over the top of the riser tube. Because this would create a vacuum if it was not filled, water is pulled from the surrounding sources. as the riser tube blocks off all the sides the only place water can be pulled from is under the UGF which again, would create a vacuum if not filled, so pulls water from the only available source to it... through the gravel. excuse the rubbish pic, but it sorta shows what i mean

Incidentally, it is possible to create a reverse UGF, using an external filter. where you put the intake tube into the water as usual, but the output tube leads down into the riser tube of an UGF, (the top of the riser tube would have to extend out past the surface of the water) this forces the water up through the gravel.

 

[Minni3]

Yeah that's the thing, the water isn't actually getting up the riser tube... and there's no airstone in my undergravel filter?

Here's the picture of it on the package:

 

[ibbledibble]

Yeah that's the thing, the water isn't actually getting up the riser tube... and there's no airstone in my undergravel filter?

Here's the picture of it on the package:

is the top of the riser tube, above the water level? as that could stop it working properly.

 

[Minni3]

i thought it had to be under water...beccause how is it going to disturb the water for aeration? The package says it does both. I remember I had it above water...and nothing happened. That's why i cut down the riser tube so that it would be under water

EDIT: wait could it be because there's gravel under the filter and on top of it? Should gravel only be at the top?

 

[ibbledibble]

i thought it had to be under water...beccause how is it going to disturb the water for aeration? The package says it does both. I remember I had it above water...and nothing happened. That's why i cut down the riser tube so that it would be under water

EDIT: wait could it be because there's gravel under the filter and on top of it? Should gravel only be at the top?

yeah thats what i meant, it has to be below the water. sorry didn't make myself clear.

not sure whether having gravel under it would change anything or not, but all the ones i've seen have had gravel only on top. so could be worth a go to see if it changes anything?

 

[Minni3]

No it's not your mistake, it's mine - I skim read way to recklessly

I will try to take out all the out from under it and see if it works!

Keep you posted

 

[monica]

Actually bettas do better w/ aeration Means they don't have to go up for air every 30 seconds
So if your Filter is creating bubbles, that is fine

 

[Minni3]

I got all the gravel from under the filter and now it is working...kinda. It's better than before at least . Some water is actually getting through and passing the sponge filled with the beneficial bacteria (yay). It's 100% efficient (more like 50%-60%) but it should do the job of keeping the ammonia levels down until the next weekly water change.

 

[ibbledibble]

with an undergravel filter, most of the beneficial bacteria build up is in the gravel itself. yours sounds like quite a strange one? not seen a UGF with a sponge filter before. so anyway, you should get a good bacteria build up on the gravel soon and that should do the job

 

[liz2]

I had one of those filters and I never managed to get it working. The airstone used to make the whole contraption rise to the surface even though it was under gravel...

 

[Minni3]

I had one of those filters and I never managed to get it working. The airstone used to make the whole contraption rise to the surface even though it was under gravel...

Your air pump was too strong. What i did was buy a valve connection thing for my airline tubing. It has a little screw on it so that i may adjust the rate of air flowing through. I have mine on the lowest so that it filters but doesn't create a lot of current. Afterall, I only have a 3g tank so I don't need a powerful filter lol.