Need help saving this plant...Pic included

Please take a look at the pic. This plant was looking healthy just over a week ago. It is a dinafem California hash plant. I had two bag seed plants die a few days ago and its symptoms started off the same way. I just assumed there was something wrong with the seeds but now this plant is doing the same things.
The plant is in a 4 gallon DWC w/ airstone, 18/6 light cycle, 12,000 lumens of T5 floros, AN Micro/Grow/Bloom at 1/4 stregnth, ph is at 5.9, room temp varies from 81-85.
Please help save this plant. What could be the problem

looks like fert burn to me.

cut back to 1/8th or 1/16th strength. add some 35% hydrogen peroxide. couple ten drops of superthrive per gallon.

(i know i know, but ive had personal exp with using it for plant recovery)

NOWitall said:

looks like fert burn to me.

cut back to 1/8th or 1/16th strength. add some 35% hydrogen peroxide. couple ten drops of superthrive per gallon.

(i know i know, but ive had personal exp with using it for plant recovery)

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I'll do a reservoir change and take back the nutes but usually when I have nute problems I can tell within a day. These nutes have been on this plant for almost two weeks with symptoms not showing up until 8 days after nutes were applied.

how warms your res water

stilljonzen said:

how warms your res water

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nothing out of the ordinary.

I would just give it some water for a while. What colour are your roots?

81-85 temp is a bit on the hot side, but should be bareable to the plant. Are you using additional CO2.

abberation said:

I would just give it some water for a while. What colour are your roots?

81-85 temp is a bit on the hot side, but should be bareable to the plant. Are you using additional CO2.

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No additional CO2. What's the cheapest way to do this?
The roots are white but I'll check again when I get home. Have looked in a day.