Yellow dying leaves

For first 2 weeks wqs given ph water 5.8 to 6. 2 then started feeding, feed with general hydroponics nutrient and cal mag, i was feeding them half of the recommend dose on the bottle once a week but they weren't growing big so started given them the recommended dose on the bottle and balanced ph to around 6, were doing good for a while till 3 weeks ago whem leave started curling up along the edges and turning yellow i stopped feed flushed and kept give ph water leaves never recovered qnd kept getting worse, do have a measure of the run off and here i am.

The biggest thing you're doing wrong is not keeping a diary... this would provide us with much needed information and the ability to guide you with some sort of reasoned advice. It looks like you've got quite a bit of a problem going on but you're going to have to do most of the guesswork here because we don't know what you've been doing.... so start looking at your pH - is it between 6.0 and 6.5? If it is, then how much nitrogen have you been giving them (nitrogen toxicity often leads to a lockout of other important nutrients). If you can put together SOME kind of information for us going back as far as you can (1 week? 2 weeks?), and then come ask your question again.... I don't think this is a lost cause but without information, we're flying blind.... Look forward to your NEXT question WITH a diary! We WANT to help!

Your ph is wrong and possible watering issues. Are you testing your run off ph?