Answer: I am surprised that your seedlings have not grown true leaves yet, (are you sure they are tomatoes and not weed seeds from the potting soil?) but here are some things to try to speed them up. Provide them with as much light as possible. Ordinary fluorescent lights can be used for this, with one cool and one warm bulb being a preferred combination but even an ordinary lamp can be of help as supplemental light if they are in a window. Alternatively, a big bright south facing window may provide enough light. Next, make sure they are not cold; tomatoes grow best in temperatures in the 60's or warmer. When you water, use tepid rather than cold water, too. Once they sprout you should emove the dome so they have some air circulation and be careful to keep the soil evenly moist but not sopping wet. Wait until they have true leaves before you fertilize them, and good luck!
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