Ph problem and plant trouble

Hello all,
Lookin for a plant master and or doc this is my first indoor grow with good genetic seeds ( i have grown outdoors with seeds collected from various bags successfully) anyway my hydro system is working well i am using a ebb and flow system with hydroton medium and techna flora nutes following the recipe for success to a letter. Theses girls are about two weeks old started under just a plain 18 in flourescent (spacesaver undercabinet type) they are now under a sunblaze T5 2' 4 lamp(grow bulbs) my reservoir is not heated but the grow room temp never goes below 67deg max temp does reach 80 once in awhile mostly stays around 75/77deg the light is suspended about 4 inches above the plants.Ok now thats out of the way the Ph keeps raising and i have to continually check it and adjust with Ph down (Phosphoric acid type) i try to keep it under 6.4 mostly at 6.0 but i only have water test kit at the moment cause of funds, I have noticed that the oldest 2 leaves are deforming and the stems are dark purple no brown yet but i would like to correct this as soon as possible and stablize the Ph here are the pics.the first is from previous pics before the leaves started to deform

5.8 ph is ideal and the ph rising is normal unless you use a nute brand with a ph buffer, also bactira in the water can cause a ph to increase to. the weird leaves is the
ph being high other than that they look good

a pH of 5.8 is optimal for ganga but 5.5 to 6.5 is okay... you might do better if you can gt it down a bit but it's okay to let it wander in that range.