Nutrients and PPM question....

Can some1 tell me wat ppm of the water my plants should be feeding at and at what stages please?
This is in a Hydo setup.

Your nute supplier should have a chart. Check their website. Here is one for FoxFarms.

http://www.foxfarmfertilizer.com/hydrofeed.pdf

I start mine in 200 then after a week up that to 300 , then when I change the water out,(which is almost 2 weeks just ph balance the water and let that go for a day or so then add nutes/bring that up another 100 and check ph ,I do that till I reach 600ppm and hold a ph of 5.8 .(all that takes about 6 weeks)Then at flower ( I TURN LIGHTS OUT for 24 hours of darkness) I change water ph balnce that and allow that to sit for 2 days (basically I'm flushing any build up,..then adding nutes ) and bring ppm up to 700, then 800 second week (second week of flowering) then 900 3rd then 1000 4th week and 1100 5th ,1200 6th and I stop there and as long as all is doing fine i raise it like that unless something comes up ........been doing hydro 5 +years (DWC in totes 6-4" net pots) and this year doing aero in Totes I don't use tap water only RO and when I did DWC I used two large air stones thats the important part dont go cheap you need lots of bubble space if you can see the bottom you need more air stones so all you see is bubbles its really key to stop pythium from making your roots slimey