Any experianced grower advice needed.

I have had a problem over the past few month's not sure what it is i have never come across it before so any help will be great....tyke....Here come the stats temp is 24/26 lights on.Plants are on a 24/7 sceduale mainly because i had problems with the temps dropping too low when lights were not on and i need to push this crop through.Nutrients are vitalink a and b veg recomended dose is 3/4 ml for plants that are in my size bracket.So i have been feeding 4 ml ph of 6.0/ 6.5.Check the ph and ppm every day and it all seem's to be fine no flucktuation.The ppm is 560.Always kept my plants at this ppm range during veg then i will push them when i flower.The problem starts with a yellowing starting from the new growth and working it's way out untill the whole leave is a mottled yellow.This was happening in the soil grow that i was doing so i switched back to nft system and it's happening again.It can't be anything to do with the plants them selfs because there all seperate grown from seed.I have reduced the feed but the problem was still there after a few week the one's in the nft system have lovely white roots help me out guy's i'm at a seriouse loss here.When i say that it is nothing to do with the plants i mean it is more in the line of something that i'm doing myself.It also has happend to more than one strain so it can't be the seeds.

maybe mag defiency look here in the plant problem section dont know what nutes youre using i use small electric heater with adjustable thermostat as my room is small keeps temps 70-80.f. my plants love it

sounds like some sort of deficiency.just by guessing with the info you provided id have to say either magnesium or nitrogen......good luck

A calcium deficiency will be present at a pH above 5.8 in hydroponic nutrient solutions. This usually causes tip burn and stunted growth rather than over all leaf yellowing. Look at the charts on post #742 in this thread. https://www.rollitup.org/hydroponics-aeroponics/254876-my-true-hp-aero-plug-75.html The more likely problem is is a result of low sulfur or iron. Iron is not readily available at higher pH ranges such as 6.0. This is also indicated as the defficiences is showing up in new growth rather than old growth. If it was instead appearing in middle to bottom leaves (older growth) then it would likely be a deficiency of either Nitrogen, Phosphorus, Potassium or all three. This would mean your EC is too low. What is the ppm of the iron in your fertilizer? It should be at least 10 ppm or the analysis should say at least 0.10 % iron.