Actually I have to back bio up here in ryan rileys book growing elite marijuana there is an entire chapter on how current research shows that you can get increased production from your plants by using lower ph levels and lower ppm's(osmotic pressure) allows the plant increased nutrient uptake or in otherwords they can really suck up whats in the solution easier then when the ph and ec are in the higher levels. But personally I have found keeping my rez around 5.8-6.1 works fine just a matter of dialing in the nutrient needs so my suggestion is to any new grower keep a chart listing when you see signs of tip burn and at what ppm level each week of your plants life untill you know exactly what they can tolerate and need after this each subsequent crop will only get easier , larger and tastier as you dial in exactly what your plants want from you in the enviroment you are able to provide. Of course optimal enviroment conditions will make care and yields even better but I have seen people get 2lbs off a 3 x 4 under 1k of lights with temps in the mid 80's and and no co2 addition and other people get less then 1lb off the exact same size table with 76 degree temps co2 addition bloom booster etc .
