Finally getting PPM meter today!!!Questions??

Finally getting a PPM meter today! I got a decent pH meter last week and plants seem to be doing alot better since I got it and am able to keep my pH down to 5.8. Now they will be that much happier. I am using GH three part and need meter now that I am into second week of grow..Plants seem to look a little on the light side tho...The leaves aren't curling up or down this time tho..just wondering if I am lacking something? Maybee it is the 1000 watt hps light? Does someone here know what it could be? Now I need a digital cam..loL......I havn't been adding epson salts or cal mag to res either...could that be it? Do I really need it. I will be testing water later first thing before testing nutes What formula should I use from this site I found? Too many to choose from...lol Need someone that knows better to decide for me? I feel wierd not adding grow to my mix like the lucas formula says??? any sugg?

http://www.overgrow.com/growfaq/t47

Use the chart in the FAQ follow it's directions.

If you are using only HPS and not an enhanced HPS bulb the plants are missing the blue color spectrum and the growth will be a little yellowish looking in color. They are not producing all the chlorophyll they should.

How far along are they now, I forgot?

what nutes are you using gh? if you have 3-part you use grow also, or you are depriving the plant of some essential nutrients that it needs to grow properly
I would suggest using the moderate/light feeding schedule your 1st grow(less danger of over nuting)...imho it worked for me...Glad you are up and running...I've been following your grow plans from the beginning...goodluck

Thanks...just got home and changed res... The bluelab truncheon meter reads ec and ppm on two different scales 500 and 700 whatever that means??? Tested water and no reading on meter....after using 3 mils per gallon x15 gallon res of micro...2 mils per gallon gro....3 mils per gallon bloom., 20 mils per gallon diamond nector ....1 tsp per gallon calmag plus..The meter light is on the CF=14.....ecx700 is 980ppm and ecx500 is 700 andec is1.4 am I allright????

I think your too high, but I am not looking at the feeding schedule you are looking at
2 weeks old I would think you would be around 250-300... I'm not sure about the conversion 500-700

according to the gh nute schedule in growfaqs you should be betwwen 400-800..I would shoot for the lower side of the scale in dwc, because of the immediate uptake through the roots...just add ph ro water to lower the ppm