Aerobuds

As A newbie any suggestions or input would be appreciated. My system consists of 2 units. The first unit consists of a Aero 9 unit with a 400w Hps. My 2nd unit is in a closet, I plan on using it for a clone room, I have a clone machine 20 with a 175w Mh. I will be using R.O. water, And I have a 265 cfm mounted in the ceiling. The only questions I have right now are. After reading the grow guides and many threads it seems people are growing in a fairly wide range of PH. Ive seen anywhere from 5.2-6.7. Where is a good starting point. I have a UV stablizer left over from a salt water aquarium I used to have, Is it worth hooking up. I plan on growing a strain that is almost pure sativa, can I take clone's and put them directly into flower after they have rooted. And lastly can someone give me a recommendation on a good Ph- Tds pen.

adderpuff

Hi Aerobuds
PH yes the range is vast and you can literally use anywhere in this range personally i have been setting at 5.8
although a lot of postings are saying lower like 5.2 witha
combination of lower nute strengths, helps the plant to sugar better.In a MJ book i read they wuz sayin as low as 4.0-as high as 9.0 befo any damage occurs
PH pens
there is a nice lill unit out that does all 3 in one
PH,salts an EC dunno the name unfortunately but its around £125
an the UV stabiliser i do not no of any uses fo it in growing
perhaps others may no.
Adder