*****First: in some books and online articles i've read it says mealworms can cause impaction, but some people here disagree. What do you think?
Second: I have an extra tank, how could i set this up to keep crickets or mealworms in to feed the gecko?
Third: do undertank heat mats come with temperature regulators?
thanks, any other info you can give me will be greatly appreciated.*****
I think its great your trying to learn as much as you can. SHows you will be a good rep keeper! Hopefully anyway! lol
Crickets i have no idea how to really keep those for a long time. We went out and got a rubbermaid, one of thge tall ones, drilled some holes in, put in some gut load and throw some fruit or veggies in there and feed the lil things to the leo's and the beardie. They usually dont last long as we dont buy huge amounts of them just yet!
As far as mealies, i would say that as long as there apropriate size you shouldnt have a problem. We havent so far anyways and almost everyone i have talked to feeds them aswell. It can be a challenge to find ones small enough for younger leos.
As far as your UTH (under tank heater) No they do not come with anyway to regulate the temps. You will definitly have to buy either a thermostat from one of the reptile shops, or if you dont want to spend the money on that and your house temps stay fairly regular go to home depot and buy a lamp dimmer switch! We use them and IMO they work great. They cost like 8 or 10 bucks, they plug into the outlet then you plug your UTH into the dimmer plug. Hook it all up and start out with the switch tunred on to about 50 to 80% on, wait a night and check your temps and adjust from there. They do sell the same thing and the petshops and they call them reostats. Just me but, its another thing that they over charge for and it does the exact same thing the 10 dollar dimmer will do.
Ofcourse the safest way to go is to buy a thermostat but for a good reliable one your looking at anywhere from 65 dollars on up plus shipping etc..
Feel free to ask questions, if i think i can help i will gladly do so!
Good luck!
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Mike & Wendy 
2.0.0 Siberian husky, Jackrussel/schitzu
0.0.1 Ball Python
1.0.1 Leopard Gecko
4.0.0 Beta's
3.1.0 Future Herper's