Humidity - Help

OK so i am doing an auto grow and my last crop of normal didnt go to plan, seemed very dry and i dunno wether this was to do with humidity or not as i am using biocanna flores ect... for nutes.

Anyways its on a 16/8 cycle with temps ranging from 72F - 91F which i know is too much i have a heater in tent to keep temps up but can get it any warmer on the dark cycle humidity ranges from 40-45 whilst the light is on and i have checked and i am guessing must rise up to 80+ when light is off, does anyone know the best way to keep the humidity at a constant level even if it means buying a de/humidifier? Anyone know a good cheap one that can just control it at a steady level at all times?

Your humidity sounds reasonable, and if you aren't experiencing mold issues, doesn't sound like a problem to me.

I'd be more concerned with the 91 degree peak temp in the tent. Over 85 degrees without CO2 enrichment is inhibiting plant growth.

+70rh at night will probably snag u before harvest.

If you exhaust the air with a real fan, I bet these problems clear up.

Keep your absolute never exceed temp at 86f. Unless you're running CO², upper seventies to 82 is best.

I LIKE my RH in the upper sixties to seventies in bloom, but then I do realize I'm in the minority. That said, 95% is too much of a good thing- soooo get a hygrostat (just like a thermostat, only for RH) and use it to control a vent fan to keep such spikes in check.

I'm confused... up to 91 degrees and you have a heater in the tent?