depending on the number of tarantulas and the size of the monitor you may be needing a larger colony. I keep mine on the top shelf in my reptile room which is a steady 82 degrees and they breed fairly well. when i've bumped them up to the low 90s they produce like crazy. and when I put them in a cooler room they slow down. I keep a constant supply of water gel with them. I give them a dry food once a week and fresh fruit once a week. removing the left over remains of fruit the next day. mold will wipe out a colony with a quickness. I keep them in 64 qt totes with a 6inch square cut out of the lid and covered with window screen for ventilation. i'm not on here much so feel free to hit me up on FB or email if you have any other questions.