UTH and heating troubles

[Jessimica]

A ambient temp of 70 is to low. Your ambient needs to be 77-82.

The hotspot substrate needs to be 1/4 inch or less.

Repti-Bark is not great for humidity. Cypress mulch is a much better choice.

Unfortunately no store near me carries cypress. Funnily enough, none of them had even heard of it. Oh Canada...

How would you suggest raising ambient temps? I've been trying to avoid a heat lamp. My ambient temps notably warmer during the day, but it's night now.

edit: the tank has nothing in it aside from substrate right now, I'm going to fill it with plants and hides, I'm hoping that will help me trap some heat