Keeping Fruit Flies off Tank Walls! Help please!

[Kurt]

You can't stop them from walking out the sides. Most of my fruit fly eating frogs are in critter keepers or faunariums (ones without vents on the sides). I put paper towels between the tops and the rest of the enclosure. If more than one paper towel is needed, then I put masking tape over the perforation between the towels. This will keep the flies inside the cage.
I would not put petroleum jelly in any frogs' cage.

[joshsfrogs]

There are a couple things you can do to lessen the amount of flies crawling up the site. The first thing is to dust your flies with a multi-vitamin and calcium supplement. The dust will weight the flies down enough that they will have to clean themselves off before they can climb up the side.

You can also keep the flies in by adding a piece of fruit to the tank to attract them.

None of these options are full-proof however.

[Kurt]

I have seen them climb up the sides even after they have been dusted. The paper towel thing works perfectly. The only problem I have had is, how do I use this method on larger enclosures? I have managed to use it on large critter keepers and a 2.5-gallon tank, but nothing larger so far.

[Bellerophon]

a feeding station as josh suggested is your best bet. Usually a piece of orange on a dish out in the open is enough to keep them occupied until eaten. If they're not eaten within a few hours then you need to feed less flies more often.