24 day into Flowering - PLEASE HELP - LOTS OF PICS!

Hi,

My fan leaves are starting to yellow and die. Just effecting fan leaves - the new and young growth looks good. Can someone please help me? Here is my info and pictures - also - how does the bud formation look so far for day 24?

1. Flood and drain 4x4 table 5" pots with hydrocorn and rockwool chooped cubes in a 4x4 tent. Tent is open when light is on with 2 oscillating fans so there is good circulation

2. Temp - 78-84

3. 20 gallon reservoir - goes through about a gallon of water a day and PPM goes up so I have to add more water. PPM range 640-760

Strains: Herojuana and Sour D - both strains effected equally

Nutes all from Botanicare at about 75% less then recommended on the feeding charts
Botanicare Cal Mag Plus - 50mg/20gal
Botanicare CNS17 Bloom - 250mg/20gal
Botanicare Hydroplex - 30mg/20gal
H202 - 50mg/20gal
PH - 6
PPM - 645

Any help would be GREATLY appreciated!!!!

Thanks in advance

Patrick

H202 is usually for flushing as it messes up nutes. It also kills good bacteria. Your ppm on cal mag is way too low. It should be 5 mil per gallon of water in res. If you drain and refill and correct cal mag it should improve quickly. Then wait a few days and refeed at reduced dose just to let plants get normal again. I personally use Peters 20/20/20 when I screw up in hydro because it gives me a fast turn around. I use it at a 50% dose or less depending on the strain. Keep in mind if you use peters it has plenty of Cal and Mag. I also use Zone by dutchmaster to help fix lockouts and deficiencies. A little Zone and some Peters and it should help, don't forget to PH correct after mixing nutes and Zone. Any chem fert or salt based fert with even numbers at a 50% dose will work like 15/15/15 20/20/20. Do this for one week or five days at least and they should be fine.

looks.like its eating itself..

Thanks for the advice desertdog. I'm a little confused - should I drain and remix reservoir nutes as follows?

1. Cal/MAg @ 5ml/gallon
2. 20-20-20 fert at 1/2 strength per gallon
3. Zone by Duchmaster
4. Adjust PH
5. Run system for 5 days
6. Remix nutes back to normal with correct level of Cal/Mag

Is this right????

Thanks