Keeping the RH at a constant

A question from a fellow grower: I have a problem keeping the RH at a constant. I do not mind 3 to 5 % variation. Problem is i get about a 15% spike. Do not have dollars to invest on state of art equipment. I have a humidifier to add and i am using these renewable moisture grabbers that help. Any neat tricks?

No tricks. But, i don’t think a 15% swing either way will hurt. Outside, humidity changes daily

I agree what exactly is the humidity range that your working with ?
Is humidifier inside or outside of the tent ?

Does it spike during lights out? This is typical. When it cools off when the lights go out, the same amount of water vapor is in the air, but the relative humidity will increase relative to the temperature decrease.