Best way I can think of is to pull the frogs and rebuild the viv. Wash the plants off thuroughly and make sure the roots are free from any soil as this could be harboring ants and their eggs. Alot of people will say that leaving the ants in there is ok, but I do not agree. ants, when in large groups, can become very dangerous to the frogs...especially in such a limited enclosure. They can make quick work of a frog in a matter of an hour or so.
It was interesting, at the Ranario in Monteverde, we had an infestation of ants as well. What we had to do (to make a long story short) was seal up the holes all over the tank where they could get in. Then the boss came by with boiling water and soaked the dirt (with all frogs cleared out) with it killing them. That got rid of the ant problem that was causing quite a few problems.
I know a guy who has lost alot of frogs to ants...I came close to losing some intermedius when ants got into their tank last year. I FREAK out when ants are even in my house, like they are now, because that means they could find my tanks....I know they can and will will kill frogs....so best to not take chances with ants.
While some darts will eat ants of only certain species, and some hobbyists actually feed certain small ants, such as the bona fide sugar ants and so-called pavement ants to the darts who will eat them, an overwhelming invasion from the outside of any species of ant is a different matter. They can disrupt not just the frogs, but the entire habitat.
You need to first trace and stop the ant invasion wherever it is coming from. Then you can remove your frogs and do the CO2 treatment. This will kill the ants, but also some of the more beneficial insects when present, as well, so it's kind of a last resort measure. Put in some "dry ice," then seal the tank tightly for about 24 hours. Air it out well before replacing the frogs.
ahh ants i had them trying to invade my iguanas cage once... all i endded up having to do was seal up the one corner better they stopped getting in...luckily i havent had an ant problem with my darts yet
this post was dead for 2-1/5 years lol
Wow. I found the ants were coming in from a poorly sealed window, I moved some of my beardie grow-out cages near it, and placed a dog food kibble in the cages to attract the ants. The beardies circle around the kibble and eat like crazy, its great. Occasionally, Ill leave an empty FF culture open on the windowseal, and come back a day later to find the culture filled with a couple hundred ants. My leucs and pumilio love em!