Why? To protect them from the heat of the halogens? Yes, take the towel off, and get rid of those halogens.
Yes, it matters. I'm sorry I wasn't more clear earlier.
What your trying to do is replicate the Sun's spectrum, indoors. The warmth is initially needed to germinate the seeds. After they germinate, and start their true leaves, the temperature can be lower.
This is a good read, especially the section on lighting:
Starting Seeds Indoors: Part 3
Don't use regular incandescent bulbs ("grow bulbs") or halogens to start or grow any plants, this type of light generates huge inter-node spacing, poor vegetative growth, skimpy yields, and could set your house on fire due to the dangerous amounts of heat these lights produce, and is the reason your plants are "leggy".
Spend your money wisely, invest in Fluorescent lighting (good), or High Intensity Discharge lamps (HID-- recommended). HID lighting such as Metal Halide (MH) or High-Pressure Sodium (HPS) supply the high-intensity light that plants need for good growth.
Halogen lighting is a poor choice for plant cultivation because they don't have good spectral output for plant growth.
This is a little technical:
A good way to measure plant growth efficiency of different types of lighting is PAReff. PAR stands for Photosynthetic Active Radiation: the wavelength range of light between 400 and 700 nm that can be absorbed by leafs for plant photosynthesis. PAReff is the PAR/Watt efficiency ratio over a certain area.
Some examples, they don't have to be Phillips just try to match the values:
Philips Advantage Fluorescent, 5000K: 1.44 PAReff
Philips High Pressure Sodium deluxe: 1.38 PAReff
Philips Dense-Line Emitter Metal Halide, 4100K: 1.38 PAReff
People usually choose halogen for the "low start-up" costs of a halogen light.
The real cost of halogens result from its low efficiency.
500 Watt halogen lighting produces about 0.08 Watt/s/nm in the green-yellow spectral region which is about the same as 80 watts of cfl's.
A 500w halogen grow will cost approx $63 for electricity, whereas a more efficient light source generates the same par value for around $10 (depending on your local prices).
Glad you received the pix's.
Don't you two work too hard, make sure you both take the time to smell the Dahlia's :)