Sounds like Leprechaun is right. Get those lights closer to the plants. You should be able to hold the back of your hand at the canopy of the plants and your hand feel comfortable. If your hand feels too hot after 30 to 45 seconds raise the light another 1 inch and re-test. The yellowing leaf tips on the older growth is most likely due to the plant using its nutrients. The other thing it could be is Nutrient Burn. Be sure not feed nutes for the first 2 - 4 weeks after seedling has popped up. Depending on the soil you are using, you may not need supplemental nutes at all. FoxFarm Ocean Forest has all the nutes you need for the entire life cycle as long as you transplant every 4 - 6 weeks.

Hope this helps a little!
ThePinkJina Reviewed by ThePinkJina on . Have enough lighting but my stems are long and thin. Need help please I was given two seeds from a friend which germinated in two and three days respectivly. My lightingfor veg is 150w mh and a few cfls. Put in an organic soil n they rapidly took off. In two weeks thing 1 grew 5 3/8 inches, the second set of leaves showed up about a week after planting and first set started to get yellow at the tips. Thing 2 has grown to 6 3/8 inches in the same time frame plus one day. They are being watered with distilled water when soil has been dry more then a day. I did add Rating: 5