Thanks very much for your advice, much appreciated.

There isn't any fresh air getting in there really. The cupboard door is left open, and so is the window in the room where the cupboard is located.
There is an oscillating fan in there, giving some air movement.
WeedyBoyWonder Reviewed by WeedyBoyWonder on . Yellow stripes, crispy leave, discolouration. Hi all, we have 2 plants under a 400w HPS. They are being given Bio-Bloom nutes, in the correct doses. The water is at around PH 5.5-6.5, 2 liters every 3 days. It will be 30 days into flowering tomorrow, but over the last few days the leaves are beginning to get yellow 'burn' like stripes. This is only on one plant specifically. I hope the pictures attached will show what I am talking about, any information as to what can be done to prevent more of this and what the problem is would Rating: 5