can someone help... confused

This currently my first grow so I'm a little lost. I have lsearched all over the web and I'm not sure what my plants might have? It looks to me like my plants might have nutrient deficiency or it could have calcium deficiency.

I'm currently running flourscent bulbs for now, since my hps ballestor just died out. I'm using foxfarm ocean forrest potting soil. I have been out of town for a week and my wife been taking care of them and she said she been watering them with tap water. The plants gets water every 2 to three days depending on how dry the soil is. The plants are 4 1/2 week old.

What do you think my plants might have? Should I flush the plants out? A couple of my plants looks like that. Only the bottom leaves are like that, the top leaves are fine. Any expert here can shine in on this situation.

I'm no expert but if that's the only thing wrong with your plant then don't worry. Especially if its only on the bottom its probably lacking a little N. The plant takes it from the bottom and uses at the top.again not a big deal I have seen way worse than that

If you said you thought it might be calcium check the pH of your tap water.

In soil the plant needs a ph of like 6.4 to 6.8 or so or else the calcium gets locked out and the plant won't take it.

If you really wanna grow that plant out go buy a pH meter to measure your water, and some pH up and pH down.

Your plants will love you for it