Hey Cathy, I just read this... You need to give more details on this the voltage, etc...

4 of the bulbs are 6500k and 4 are 2700k if that's what you mean. Thank you for replying.

6500k and 2700k are the color temps. Are they T5HO?

fluorescent don't produce a lot of heat so I'd get them as close as I could. Maybe 4-5" away.

Thank you I have six trees but some of the leaves on two of my trees, blood orange and a grapefruit are drying and curling. Do you have any idea what could be causing this to happen?

How close are the lights now? Can you post some photos? You may be underwatering.

Here are the pics of my trees. My husband and I made this little grow room in the garage for the trees for the winter. We foiled all the walls. The light is 9 inches from the tallest tree. Maybe that is too far can you tell. I don't know if you can see some of the leaves curling on the trees that I took a single pic of or not. I purchased some old broilers from garage sales to put under the trees to catch the excess water. Good idea hey? I have that gritty mix in the trees and I am new to this so I don't know how to tell when they need water. Can you please help me. I give them 1/2 gal once a week. The temp and humidity l check daily and they both have been in the mid 50's. I appreciate any help that you can give me. Thank you very much in advance.

You need to decide whether you want your trees to do semi-dormant or to continue to grow and produce fruit. Your current conditions (low temps & low light) encourage dormancy.

If you want growth, you will need higher temps of at least in the 60's. I do not know much about lighting, but it seems to me that you would need at
least another set of 4' 8 bulb t5 lights, maybe two and closer to the
trees.

Keeping the temps in mid 50's may be your problem because that is too low. Roots don't work at that temp. and that causes the plant to drop leaves. Try 60 F instead without changing the amount of light or maybe adding one bank of lights. Use warm water (about 80F) for watering and use a humidifier, if you are not already using one.

See http://www.steffenreichel.homepage.t-online.de/Citrus/lime2.pdf.

You can tell if the trees need watering by digging down a couple of inches and feeling the soil mix to see if it is damp. Make sure that when you do water, some water comes out of the drain hole at the bottom.

What are those things on top of each pot?

Thank you very much for your help, I will make a few changes. The things on the pots are little dishes with vinegar and dish soap for knats. It has helped a lot. Do you know of any other ways to get rid of them?

I had a gnat problem early this year. I've tried neem, safers trounce, diatomaceous earth, and mosquito dunks.

Mosquito dunks worked best for me. I bought them at the hardware store. Just crumble up one of the disks and spread it on top of the soil. Each time you water, it should re-activate the dunks kill off any gnats.

Also try to let your soil dry out as safely as possible between watering. consistently wet soil is a haven for gnats.

Thank you very much for the information I will try this

My tree

The little dishes of vinegar are a smart ideal. I might have to try that!