important

is it essential to have a fan in your grow room? i have one 400W bulb over 4 plants, i am thinking about putting two more in there, we air it atleast twice a day and check on the plants, someone mentioned that the plant will go straggly and not solid buds, is this true? and can we prevent it without the expense of a fan, much appreciated.

You need the fan so the plant will respond to the breeze by strengthening its trunk/stems. Without it they won't be able to support their own weight when they get older.

ya, do you mean intake/exhaust or indoor circulating fan?