My plants have been in soil for a week. Is 150 ml ...

I would only water again when the surface is dry and only water around the seed 150ml sounds good

It sounds like to much, But it depends on how dry it gets. How much heat/humidity is in the grow area. You only want to water when the soil dries out 1 knuckle deep. Looking at your plants. your light might be a bit to close. when the leaves start to point up they are receiving to much light. you want them to go sideways or slightly curved down.

Dont water them with a Timer! Try to water them only if the Top soil is drying out (but not to much oc) rule of thumb is litteraly only watering them when half your thumb feels dry Soil if you stick it into it. Roots need some Air to grow and so on...