4 foot by 4 foot by 4 foot tank

[Tony]

Hi ron i need your help or any input you can spare for me. i have a 4 foot by 4 foot by 4 foot tank with co2 and a vent/ac system and right now im using 2 floresents and the inside of the tank, the tank is all wight, i had a lot of alge growth and the tips of my leaves were curling up and turning brown on the older sets of leaves so i rinsed out the system and leached it because i read that it could of been too much nutrient so i added fresh water and rinsed the roots for about 5 mins and added some grow food and now the brown curled up leaves turned into wight curled up leaves, can u tell me if i don't have enough nutrient or is my ph messed up or is it just the color of the already edad leave any idea at all???. thanx love ur site