Hey
@Digitalis and welcome to AFN my man

Stealth and security is top priority, I have the same size tent as you (also UK as well ) so any help i can give please give me a shout by tagging me (
@Slater ).
The dehumidifier is a good idea but it will add some heat into the tent and your going to be running a hps in a shed coming into summer and thats just when you need it the most.
This is the mini one I have, doesn't put out loads of heat but will add some to the tent. Could be the thing your after. Or you may have to go old skool, cups of rice, news papper etc... those mini dehumidifying tubs you get from pound land seem to do the job, I used them on my first grow. Probably will again sometime this summer.
Have fun dude... still plenty left on this
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