Have you read the care article on Pacmans. The care sheet is within the care articles. Misting once a day is seriously not enough. I'm telling you just because they can handle levels at 60%doesn't mean they should be kept that way all the time. Trust me I have a Zoo Med Hygrotherm. It controls the level of heat and humidity within my Pacs enclosures. If the humidity falls which it does quite often it kicks on my Reptifogger to raise the humidity. I even have the screen top covered 3/4 of the way with Plastic wrap to hold heat and humidity in. I suggest that you buy a digital hygrometer as they seem to be more accurate. It is more ideal to maintain certain temp and humidity ranges as it gives these frogs the environment the really need for proper developement and growth. Their ideal humidity is 70 to 80% and the human eye or bady cannot accurately measure humidity levels just by sight or touch. There is a reason why when buying and careing for these frogs that it says a tempreture gauge and hygrometer are required to measure the levels within the enclosure. There are several of us experianced owners and not to mention breeders that will tell you this.
You say they don't seem to work and they'll end up on your floor. These devices are supposed to remain inside the enclosure with your frog. You don't take them out and then every now and then place it in for a reading. That doesn't give a very accurate reading and it could be too late by the time you realize its too hot in the enclosure or way too dry. Touch and sight don't measure accurately. I realize thing have been fine so far but you are taking risks in this method. And you should never have to open the tank to let humidity out. You can't read how humid it is in the tank so how do you know its to humid. They are tropical and love very humid environments. Without proper humidity levels they can develope problems later on. I'm trying to help.
