Athosanswered grow question 6 years ago There's a reason most start in smaller cups, and that's the risk of over watering when you soak all the pot.
As you are going to be up potting, there's no need to feed for quite a while, let the plants feed from the soil. The 1 gallon pot should last you 3 or 4 weeks before needing to up pot. I would say that with a 7 gallon pot, you should have 8 or 10 weeks before needing to feed anything. When you do feed, to so every 7 to 10 days in soil.
Now watering, I keep records of the amount of water my plants consume daily on average; also, you should give enough water for 4 to 5 days. Keep in mind that higher temperature will make this numbers go up and colder temperatures will decrease the need, but all in all it will give you and idea of how much to give them.
Considering day 1 when they open the first set of true leaves...
Day 1 to 10: 50 cc of water a day (usually I give 200 cc or 7 oz every 4 days).
Day 11 to 17: 100 of water a day (2 cups (14 oz) every 4 days).
Day 18 to 24: 150 cc (5 oz) of water a day (1 liter (1 quart) every 6 days).
Day 25 to 35: 200 cc (7 oz) of water a day (1 liter (1 quart) every 5 days).
Day 36 to 40: 300 cc (10 oz) of water a day (1.5 liter (1.5 quart) every 5 days)
Hope this helps.