Humidity Problem

I can't get my humidity down to the 40's where I need them. It's 52-66 all the time.

I have 2 600 w lights being cooled by a 400 cfm 6" fan. Temps stay between 68-80.

Then I have a second 400 cfm 6" fan extracting air with a can filter on. I have 3 passive holes near the floor of the room the size of a room vents.

The room is 5x7x6.5. Based on everything I've read I should be fine but humidity still high.
BTW: Tried dehumidifier but the heat it emits is too much for me to use in there...plus it uses a lot of electricity.

Please, if anyone can help I'd really appreciate it. Thanks.

maybe use smaller pots next time..i noticed when i grew in big pots my humidity would jump..and maybe increase your fan speed or get another one for better circulation

I had the same problem until I started bottom feeding.

Think about the opening of your pots. My flower pots are 18 inch across, so thats a lot of "wet soil/moisture" exposed to the open air to obsorb.
With bottom feeding, the only exposed moisture is from a few quarter size weep holes on the sides.
Less exposure= less moisture= less humidity.

Bottom feeding is a lot better for your plants anyways.
1.It reduces build up in the soil.
2. It reduces humidity.
3. It's better for the plant since it doesn't work as hard to find/get the needed juices.

So right now I'm using 2 gallon pots with coco. I have a total of 16 of them in there.
After this grow I'll set it up with 3x3 trays with hydroton.

I'm watering by hand this grow...Is there anything to do in the meantime?
When I go to the 3x3 trays in hydroton will that help?

I really don't understand bottom feeding. I do understand having all that coco wet will make it more humid, though.

Well whats the humidity of the air you're pulling in?

You never said what, if any, problems that your high humidity is causing. If it aint broke don't fix it. As long as you have good circulation in your area and the plants are happy, I would just leave it be.

get a couple of clip on 6" fans going to move the air around in addition to the inline can-fan which will keep the heat down but not move the air to help dispense the humidity.

I've read that if humidity is above 60% it can produce mold and stunt plant growth (stomata closes). Humidity now gets as high as 73%. I'm going to post some pics soon so you can see the setup.