RBI's CB-70 tub question

For those of you that have this rack i need some advice. I am having a terrible time getting the bottom tub to match the the other 2 tubs in heat. The bottom tiub seems to be about 4-5 degrees off the other tubs. Does anyone else have this problem and if so how did you deal with it.

I don't know if this may be playing a role in why the two females still atren't eating, i've tried everything. One other question would the fact that there are no hides in the tubs cause them not to want to eat? If i throw hides in there is it a better chance they will start eating??

Where is the placement of the rack? directly on the floor? on tile or carpet? in front of a drafty area (window, hallway, etc..)? Where is the probe for the thermostat located? It would help if you raised the rack off the floor (assuming that is where it is) by at least 10". If you can, place the probe from the thermostat behind the tub second from the bottom of the rack.

I have lots of these racks. your best bet is to put them on an insulated base.... but still the bottom tub is always going to be a couple degrees colder then the rest. It really isn't anything to worry about. temperatures do not have to be as exact as many on this site like to preach.

The tub actually has 2 probes. I have one probe placed on the heat tape in the top slot and then the other probe placed on the heat tape in the second slot...this is a 3 slot tub.

The racks is up off the floor about 12", i have it raised by landscaping blocks and then a thick piece of plywood as the base. The thermostat is set at 99.5 which is probably hotter than the top two spots need but it heats the bottom up to close to the right temps. I just know that from the records that came with the two females when i bought them the last time they eat was October....so even though i know everyone says not to worry it has been close to 8 months so it would be great just get them to eat something. Would hides make any difference in getting them to eat???

how old are they? that is a BIG tub for a younger snake.

The two females are 1460 g and 1268 grams... however i have a 460 g male in the third spot and he's doing wonderful.

yes, I would put some hides in there that they BARELY can fit in. what are your temps inside the tub and how are you measuring them?

My rack does the exact same thing and I email Rick at RBI about it. He stated it is hard to get each tub to match exactly but they do their best. I basically put my one BP that seems to like cooler temps in the bottom tub. They all are doing well so it's working ok for me.