ok, well as i told you i have installed a hygrometer and it was reading 60%. well i have just noticed it has creeped up to just over 70%. i opened the viv doors for 5mins to lower it but need a permanent solution. below is a pic of my viv and the water bowl is 4" diameter only about 1/4 full. The temp is controlled by a pulse stat and set to 32*C the viv is 30x15x15 if this helps and the heat mat is on the right, with the lamp (15w) coming on for a few hours at night only.
I have encountered the same problem with my bugs. Here's a few things that may explain/solve it:
Is the viv in direct sunlight at any point during the day? If so the move the viv so that it isn't. The sunlight beating down causes water vapour to be created from the water bowl.
Is there adequate ventilation in the room? It helps if there is a gentle breeze around the viv. This stops the humidity building. Possibly instal either more vents in the viv or one of the little viv fans.
Is there a tumble dryer nearby? Humidity caused by our tumble dryer caused us no end of problems with my Aussie *****ly sticks.
May sound like silly things to check but I encountered a few problems like these in the past. Also try making the water deeper in the bowl. If the body of water is deeper it is harder for the water to vapourise.
Hope this helps and if all else fails I've got some baby african land snails that would love to live in that humidity.
p.s. Just noticed that there is only one vent in the back of the viv. Bung another one in the back behind the hide below the vine/branch about an inch above the substrate and you should get your airflow and reduced humidity.
the substrate is bark chips but im gonna switch to beech chips cos aspen is like rockin horse poo where ive been looking, plus i got loads spare as i use them for my corns.
going to pop another vent in to improve circulation also.