Undergravel Filter

[andyboy!!]

hi

i've only had internal filters not an undergravel.

i know how it works, but were does the dirt go and how do you clean the tank? do you still use gravel cleaner or just change the water

i am thinking of getting a small-ish tank for a betta. the tank has an undergravel.

thanks very much.

andy.

 

[bubblesburst80]

i have womdered the same myself

 

[fourthtimelucky]

I haven't used them myself but one of my friends has -- the gunk is sucked downwards into the filter through the gravel, so I guess that limits the depth of your substrate, and you have to vacuum the gravel thoroughly and often to stop the filter getting clogged up. Someone with more experience of using them shoudl be able to give you a bit more info though!

 

[xxBarneyxx]

That is exactly right. The water is sucked down through the gravel which acts as the filtration media. As such you need to make sure you gravel vac regularly to stop it getting too clogged up.

RFUGF (reverse flow) works a bit better as rather then sucking the through the gravel it pushes water up through it from underneath (which stops so much detris building up under the ugf plates).

It can actually be very effective and I remember my parents and sister keeping fish when I was a kid using UGF's and the fish where always healthy and long lived.

The problem with UFG is that they work great ad a biological filter but not so great as a mechanical one. If you just have a betta in there though this shouldn't be a problem.