flower dropping in hydro grow

[Guillo1]

So my plants seem to be dropping 100% of the flowers so far. They have a ton of flowers and flower buds. Plants keep on getting bigger and bigger.

Here are some parameters to see if maybe I'm doing something wrong. Temp during the day averages around 70-72 deg and when I don't turn the heater on at night it gets to a low of 66-67 deg. My ph is kinda on the low side 5.8 to 6 and I'm using GH Maxibloom dry nutrient. One setup has nutrients at 900ppm and the other has it at like 1100ppm.

Since the plants got so big I ended up placing a T5 fixture with 2 6500k bulbs. There is no way my T5 fixture can light all 3 plants. I never thought they were gonna get so big and bushy. I still have the LED light the top middle of the plants.

Here are a few pictures. I am open to any suggestions

 

[willard3]

Flower drop probable causes:

1. Day temp too high >95F
2. Night temp too low <65F
3. Too much nitrogen fertilizer
4. Too much water
5. Low light levels (reduces fertility).
6. Very low humidity (reduces fertility)
7. Poor air circulation (air circulation contributes to pollination).
8. Lack of pollinating insects.
9. Size of pot
10. Too much mineral in feedwater.
11. Too much grower attention/anxiety.