Without maintaining proper temperate & humidity thorough out your grow from seedlings to smoke! there will be no chance for greatness until you can dial it in and control your environment.
Don't cheap out in this area when purchasing exhaust/ oscillating fans or dehumidifiers.. These are key items that are necessary and they will make the difference between success and complete failure with your grow.
Test and replace your aging thermometers and humidity sensors with new accurate working devices.
Here is a quick 4 min read that you may find helpful.
Here is what I use.
This is a fantastic dehumidifier that is worth looking at and is worth the money compared to alot of the junk that is available these days. This is a perfect size for a 5x5 that will get yout RH down fast and keep your tent in the perfect range when most needed with ease!
Adding heat & humidity is easy! I use a wicking bucket and a fan to add the moisture I'm looking for and moving the air around the tent. Its winter here and a little cooler than normal so I'm using a space heater set to 80