Ventilation???

[growallday2012]

Hi, a friend of mine had a grow up and running a few months ago and he had a vent system intake/outake
which he ran simultaneously with the lights.
He ended up getting mould on the tops of the pots(growing in soil) and i was wondering if this had anything to do
with the ventilation being on 18 /6(veg) and 12/12(flow) with the lights?
I had read that some choose to have it on a couple hours when the lights are on and thats some growers choose to have
it on for longer but none had it on in conjunction with the lights. I pointed this out to him and he said the reason for him having
the ventilation on the same time as the lights was that he had no c02 system.



Any ideas if this was the right thing to do or was this the cause of the mould?


Thanks

 

[superstoner1]

sounds like it is from light exposure.

 

[growallday2012]

sounds like it is from light exposure.

How do you work that out?
Why would you get mould from light exposure?

Thanks

 

[supersillybilly]

Basically not enough air flow.....ditch the intake and have double extraction.

 

[Brokeoldbloke]

Over watering. If the top of the soil never drys out then you could get mold. And yes running your fans 24/7 and moving the air around would help.

 

[superstoner1]

thats why you should always cover any dirt, rockwool , jiffy pots with something like hydroton or just make a cover for it. it will mold when exposed to light.

 

[hotrodharley]

Ventilation on 24 hours a day. No exceptions. Unless you can get the plant to cease transpiration. Move air and lot of it.

 

[hotrodharley]

thats why you should always cover any dirt, rockwool , jiffy pots with something like hydroton or just make a cover for it. it will mold when exposed to light.

Those don't really mold as they are inert. Being inert they cannot fight mold and their surfaces support its overgrowth. But same principle and you are right.

 

[Warlock1369]

Was I mold or mildew? The green on RW isn't mold it's mildew. Not harmful but feeds off the nutes needed by the plants.

 

[growallday2012]

Was I mold or mildew? The green on RW isn't mold it's mildew. Not harmful but feeds off the nutes needed by the plants.

Thanks for the all the feedback.
I think it was mildew cause the green stuff was a healthy even green which he just scraped off and put new soil on top but it always came back.
He had the plants in 6 litre pots which is about 1.5(US gallons) and every time he would water/feed them he would give EACH plant a litre of water which flooded the bottom of the grow tent and took about 4-5 days to dry up.
I think that this caused nute problems and took the plants far too long to absorb all the liquid(when watered) and burned the plants as the roots where sitting in feed for at least 4-5 days(when fed) i pointed this out to him on numerous occasions and he said to me that he knew what he was doing.
Can someone let me know if this was the case and how much water he should have been giving them?



Thanks

 

[Warlock1369]

4-5 days to dry or not be soaked? A simple handfu of perlite mixed in soil will help with draining. And letting it flood the tent everytime is a bad idea.

 

[Red1966]

thats why you should always cover any dirt, rockwool , jiffy pots with something like hydroton or just make a cover for it. it will mold when exposed to light.

You're confusing mold and algae. Mold doesn't like the light.

 

[superstoner1]

oops. stoner moment.

 

[Red1966]

You're forgiven, but if it happens again, I'm taking your bong away.

 

[growallday2012]

4-5 days to dry or not be soaked? A simple handfu of perlite mixed in soil will help with draining. And letting it flood the tent everytime is a bad idea.

Thanks, i pointed out that it was a bad idea to flood the tent aswel, he had 5 plants in pots with no saucers and 1 plant in a pot with a saucer.
Everytime he water/fed them the ones without saucers leaked a lot of water and the one with the saucer not so much.
It took 4-5 days for the tops of the soil to dry but the soil was still damp 2-4 inches below surface of soil.
Everytime he watered them he would give them 1 litre water EACH
Everytime he fed them he did so with the feed diluted in 1 litre of water because thats what it said on the back of the bottle.
The plants where in 6 litre pots, would giving them this much water cause damage to the plants?

IN BLACK AND WHITE DO PLANTS IN 6LITRE POTS NEED A LITRE OF WATER EACH EVERYTIME THEY ARE WATERED?????


Thanks