Can you help identify the issue with my plants?

I transferred my rockwool to the 5 gallon deep water culture buckets around 10 days ago. A few days back I saw the leaves were turning quite yellow on the plants and thinking it might be light burn raised the lights to around 32 inches above the plants. Does this look like light burn or am I perhaps putting in too many nutrients (I have added 1ml of advanced nutrients per liter of distilled water).

I would spray the leaves with a foliage solution. Ie calmag and b52

What's your ppm

I am such a newbie to growing hydroponically I actually didn't even consider measuring the ppm. I assumed that by using distilled water and mixing the nutrients at 1ml/L that it would be a reasonable ppm. I have just ordered a pH test kit, would you suggest I also add a ppm meter?

I would definitely recommend a ppm tester(blue lab). If you're always going to use advanced nutrients that are p.h. perfect, you dont really need a p.h. tester. Both my testers are blue lab

Thanks very much for the advice, I will pick up the tester you recommended.

Bluelab Guardian Monitor is the best investment for anyone doing DWC

You got an algae bloom on your rockwool cubes. That's not good. Might be the issue.

It looks crispy to me. It can't handle the nutes yet.

@Southside112 Yes I believe I made the mistake of top watering too frequently after initially transferring the cubes into the buckets.

@70's natureboy That was my thought as well. I am thinking there may have been a bit of nutrient residue leftover in the bucket from a previously aborted attempt to start a grow a few months ago. I don't really understand how I could have overdone it on the nutrients with what I have added this go around though. I have been using Advanced Nutrients Micro, Grow, Bloom. Since transferring the seeds to the dwc I have added 1ml of micro, 1 ml, of grow, and 1 ml of bloom for every liter of distilled water. Would it be advisable to take a plant of nutrients entirely temporarily for it to recover from nutrient burn?

Thanks guys