I am not saying you need to buy a more expensive light, buying a few more CFL's would make a big difference, and for what a bubble cloner will cost to make you could get at least one more light, and more likely two more. Trust me, your biggest bottleneck is your light. Don't worry about stuff like cloning till you have more light, especially considering that you can clone in a cup of water. As far as flowering, you typically use a different ratio of npk.They seem to be growing from the light at a rate that is great for me. Although a better light would be nice, it is expensive. Also, I would need a bigger space than what I have to control the heat. I'm just concerned with the rooting of the clones ( I dipped clones in rooting hormone) and can I flower using a Veg nute setup.
Also, I'm not sure how versatile your pump setup is, but I would consider setting it up so they are only getting watered every day or two (or less). MJ likes to get nice and dry before being drenched again. My plants can go as long as 4-5 days between waterings depending on how hot it is here, when I water I really drench them, saturate the soil very well. They do very well with this watering regiment. I think your leaf issues are a combination of things, but nute burn would be #1 on my list of culprets since it doesn't sound like you ramped up the dosage, and with an auto drip system running that often you might be releasing them faster than you think.