Watering help

I agree smaller pots and then up plant into bigger ones, this way its hard to over water. I tent to start in a yougart cup, then 1L into 1Gal over to 3Gal and up to 7Gal. But if the medium has enough perlite/drainage in it. it should not be a big issue. Good Luck!

Best to start them off in small pots to avoid overwatering. Then work your way up

My 2c is water less than you think. It is way too common for people to want to fiddle and water tiny seedlings way too much and drown/stunt them.

Hello mate, you have different signals from the plant if she is thirsty. The first is on the leaves if you see them pointing the ground she has too much water, if they are pointing overhead she needs water. Try to keep the leaves parallel to the ground. The new leaves are also a signal, if they are close she is thirsty but it could be also for the temperature too high. The best method is to use the tool to valuate the humidity level of the soil but you can learn to do with your finger. Try to keep them warm in this stage or they will go slowly. Good luck and happy journey!

They are looking good. Your soil looks kind of wet so wont need water for a few days depending on how hot/dry it is. Luckily those fabric pots should dry out fast. Those small pots are not going to last the plants very long unless you are feeding them nutrients, and are just growing them relatively small. When you go to transplant, I recommend just cutting the pot away so as not to damage the plant's roots too much or have a struggle. I saw you are worried about C02. That is the very last thing you need to worry about. You are right for wanting to know more about water as it is one of the most important things. Start thinking about a drying space now not later