HELPPP please...

i had 2 bluecheese and 4 shaman and 2 churches and they are ALL dead, except this bluecheese which is on the way.

I really cant figure out what is wrong with them .

a week or so ago it was fine n all and now its half dead.

im growing in 1cm RC cubes under a 250 metal halide, air circulation is good and temp is between 22-24c.

A+B iconic @ 1/2 strength,
oxy-plus - 10ml/day {tank is 20L}
nytrozyme - {as directed on the bottle}
gurdian angel - {as directed on the bottle}
superthrive - {couple of drops in tank}
canna trichoderma. foiler feed 2-3 times per week

the rest of the plants died befor i started adding nytrozyme, guardian angel, superthrive, and trichoderma to the tank so i guess they have nuthing to do with it.

this bluecheese was the youngest one of the lot as i added it round 2 weeks later than the others and it was holding up. till a couple of days ago.

i strated off flooding 1x a day, moved up to 2x and now i have dropped it down to once a day.
========

lower {older i think} leaves start to yellow from outside and work their way all over, and it happens rappidly over a couple of days, then the ones above them start to do the same and now i can see that even the top are starting to yellow on the edges tho its very slight.
the plant has not grown at all for about a week, since the lower ones started yellowing.


the yellowing is really bad on the lower ones.
stems are dark purple which i think is just normal.
i have already removed 2 lower leaves as they just got tooo yellow and they were the biggest leaves on the whole thing.


i have no idea what to do please help.
iv flushed it today with superthrive/guardian angel and about 1/3 strength nutes to see what happes.

any suggestions or ideas please, need help fast.
dickdasterdly66 Reviewed by dickdasterdly66 on . Help please, 8 plants already dead, one left :(. yellowing or n def. or sumthin HELPPP please... i had 2 bluecheese and 4 shaman and 2 churches and they are ALL dead, except this bluecheese which is on the way. I really cant figure out what is wrong with them :(. a week or so ago it was fine n all and now its half dead. im growing in 1cm RC cubes under a 250 metal halide, air circulation is good and temp is between 22-24c. Rating: 5