Thank you for your respond...the ppm of the water before adding anything is 30...my grow room is free of insect im very positive about that...i did calibrate my combo meter device before use..and i did so every once in awhile to make sure it is accurate...its just throw me off as mentioned in the initial post if i drop the TDS tester along with the PH tester it will change the ph of the water will jump about 7/10 (.7) of it..not sure why...the distance from the light to the top of the plant is about 2 ft. ... since i started from the clone...this is what i did..

I have 25g rez. -- I added GH 3part M=200ml, G=200ml, B=200ml. added 20ml Superthrive and 200ml Hygrozyme...and i've been spraying Growth excel daily..

about a week ago my friend gave me some B-52 so i added to the rez. 4 days later I start to notice this symtom...

disrupted86 - what is the ppm of my water should be before adding anything? how can i change it?

Yes, its a good idea to get a cheacp ph tester for comparison i will do that tomoro..