Thanks for the reply, i set my timmers for 16 on and 8 off, and there about 7in tall now. when should i switch my cycle to 12/12? will the two 400w HPS that i have be enough light for them? and one more question, im using all of the nutes that you have listed and the same amount, what on average is your yeild for the 8 plants? thanks agian, and ill try to get a few pics of my set up, up.