Mexican Black Kingsnake question

I just got a baby Mexican Black Kingsnake today and I don't have a thermostat for the UTH yet (getting from the post office tomorrow)
So I'm only using a 50w overhead red infrared bulb since the UTH isn't plugged in.

My question is this, right now the temperature under the substrate (2 sheets of newspaper) is 85.5F on the hot side, do I really need a UTH?

He's in a 5.5 gallon glass tank.

Thanks in advance.

I'm no expert, but I'm pretty sure I've read on here that would be fine.

The cage could be so small that it doesn't need that much heat sources, on mine I only have a UTH and the temps stay where they should be, I'm guessing that the other way around will be comfortable for the snake

Thanks for the help.

I'm a bit confused, some care sheets say 82F on the hot side while some say 88-90F. If anyone who has one please let me know your temps please. :)

Where I bought him from said mid to upper 80's F.

82-90 on the hot side as long as he can get out of the heat.

It seems that a 50 watt bulb would be providing more heat than you measured on a tank so small.

Check it again. A 25 watt would probably be enough to provide a hot spot in the 85-90F range.

They can do fine at cooler temps too.

They're easy to keep.

Ok thanks for the info!
I have the 50w raised ~2 inches from the top. They didn't have a 25w :weirdface, I'm going to check at another store tomorrow though.

My hot side is currently at 84.4F, I'm using a digital thermometer.

Thanks again!

Where are you measuring? If the thermometer is not directly under the light the temps will be lower than they actually are.

You need to put the thermometer directly under the light, not off to one side, to get a good measurement.

Ok, I re-measured and right under the light it was 92.6.

I raised the light a lot more and now the 'hottest' spot is 89.5 and the coolest part of the tank (corner opposite the light) is 76.3.

Also keep in mind that this temp can vary night to day. It may well be hotter during the day than it is at night since it's warmer during the day than it is at night and the bulb doesn't have to work as hard to heat a given area during the day as it does at night.

Anyway, I think you've got a handle on it.

Thanks again for all your help, it's greatly appreciated. :)

I'll recalibrate tomorrow morning with the new light etc.

I keep my mexican black in the snake room on the top shelf of a rack with no extra heat. His tub stays a constant 83 and she does fine. They are pretty hardy snakes