Everything looks great. Don't feed until the cotyledons start yellowing. If you can drop the temp a few degrees during the day, you might get some better growth. Your lamp height seems perfect, I have the TSW 2000 and have to have it 30" up in the beginning, so you're probably right on at 25".
Last thing, if your tent temp is 81° then the temp in those domes is probably 5° higher. That's pretty hot. If your RH is over 50% in the tent and you can lower the temp, I'd remove the domes. Either way, great start!