Vertical NFT Flowering Problems

Hi, I have two plants that are 3 weeks into flower(12 on/12 off lights) and are looking sick, and im not sure what the problem is. Any help would be appreciated, I have set up two five gallon buckets on top of each other, using the bottom one as the res. I drilled 2 holes up through the top bucket for the drainage tube and for the watering tube. I ended up using gravel for the substrate. Im not sure if that is what is causing all the problems.
Growing Vertical NFT
Medium is Gravel
I am running a constant flow of water through the gravel
Indoors
8 bulb t5 fixture with 4 bloom and 4 grow bulbs about 4 inches from plants.
RO water
Plant is 2 months old aprox.
I am using 100ppm of calmag, 100 ppm of ionic bloom.
Water ph is checked everyday and is at 5.7
Air temp during the day is 75 at the hottest and at night 68 at the coolest
Right now the two plants are in a closet with a fan blowing on them
water temp is about 75

are you aerating the water in the res

No, I was roughly following stickyattics guide to beginners NFT. Could not having the water aerated in the res be causing these problems?

You have to run your calmag up to 250ppm on RO water.
Gravel? That's not in the guide. Hydroton is the correct medium for that. And the pot size is supposed to me smaller. You have the looks of a fert burn/salt issue, and the interstitial spaces between your particles, from what I can tell, are insufficient.
How often are you changing the reservoir?

Today I increased the calmag to 250 ppm, and yes I got cheap when I was trying to follow your grow guide and got Gravel, which I think that you are right stinky when you say the gravel doesnt have enough spaces inbetween. I change my reservoir every week. Stinky will I be able to make it through the flowering period using gravel? Last week I got a little nutrient happy and put in 250 ppm of calmag and then 550 ppm of ionic bloom and that is how the plants started to look like this. Thanks for the help

ionic bloom up to 550 or 550 + 250? They do look real burnt. I'd do a res change and always try to inch up your nute strength SLOWLY.
I also recommend running cannazyme especially with the small spaces!

I had been slowly giving them nutrients and they were good all the way up to 700 ppm, but the last res change I added to much ionic bloom 550 ppm and didnt want to drive back to the store to get more water. So with the nutrients should I put in 250 of the calmag and do half strength on the ionic bloom till they start looking better. Also I have Hydroguard is that anything like cannazyme and is there any harm in using it. Stinky should I also have the res aerated like the person in the fist post said?

If your res isn't cascading vigorously and you can see bubbles and turbulence where the return re-enters it, definitely hook up an aerator.

Ok, I got the res changed and put in 250 ppm of calmag and half strength ionic bloom total ppm is around 450 and ph is 5.7. Also I took off the drainage hose so that the water would cascade into the res therefore no need to aerate the res. Leaves are starting to get worse but non of the new growth seems to be effected. Ill post more pictures tonight when I can function properly. Got some blueberry last night and OMG I have a new fav strain, ive been in the clouds for the past 12 hours.