Have to get humidity down: glass tops or canopy?

[Delphinus]

40% is going to give you HUGE condensation on the windows when it's -20 or colder outside. At -30 like it was last night there's pretty much no way to avoid wet windows unless you have maybe 10% or less but that's going to be pretty uncomfortable. I have about 20%-25% right now which is enough to keep the windows dry at -23 but not at -30 like it was last night. Phooo that was a cold one last night.

Originally Posted by Coleus

My humidity level is at 40% right now but i still see the water condensing on my windows. Should i concern?

[KevinK]

ok so we also had a steady 60 to 65% (tank +sump would be apr 450 to 500 gal)

I then both a 50Pint dehumidefyer and run it for 2 days, nothing realy happening,

as I had a pipe in the sealing of my fishroom, but never did anything with it, I both a 9 cubic metre fan for $ 20 and have it running all day.

as my tank has a canopy (sort of) it is a inwall tank that from the livingroom has lids I can open, but behind the tank I have a filter room, where everything is open.

now running the fan in the filter room, I create a negative presure in the filter room (checked it with some smoke and was holding it in frondt of the lids in the living room, where it was drawing the air into the filter room.

with the effect the vent is making, the air in the filter room is going out (9 M3 minus friction and presurisin the pipe, I think about 3 to 4 M3 is leaving a minute.

the filter room is nice and comfortable, in stead of overwhelming with moist air, the humidety is down to 35 to 43% withing 2 days.

cant beleave we had the tanks running for about 16 monjths without any fan

luckely we cant find any mold !!!!!!!!

overall, I think when you put a lit on top of your tank with a vent hole, suck the air out of it by creating negative presure, and you will drop your avarage humidety drasticly

this option cant be expensive, as in worst case it is gust a plywood box, and you can make it as fancy as you want.