My main concern is if I am giving enough nutrients and water. I didn't find any charts stating how much ml of water per day is required
With coco, you just water and water and water. Don't worry so much about overwatering - it should be so well-drained it is almost impossible. I suggest you water 2x a day for now, making sure to get runoff with each watering. There is a formula/rule-of-thumb to put in about the volume of the pot and get back 10-20%. Just be sure to get runoff. It is important to not let coco dry out.
I have been following the GH charts, mostly, and diluting my mixture with another couple of gallons of RO water. Mostly because I mix nutes in a 10 gallon tank (with 11 gallons in it) then put it in a 14 gallon reservoir. I top off the reservoir each filling with some RO water, intentionally bringing down the EC. Currently EC is in the 1500 range, but as 1700 when mixed in my tub.
My thoughts on this are that as long as I am feeding the plants often (currently 5x/day), they will always have nutrients available even though the EC is lower than recommended by chart. (Hence safer. I look at tip burn closely and reduce EC if I see signs.) By the time they have pulled nutes out of the water, another feeding replenishes them.
That said, when you plant a seeding into a big pot, it takes off slower than putting it in a solo cup for a week and then transplanting. But once it takes off, it's going to really take off, if everything is in balance.
Here is a quote from cocoforcannabis.com on the subject of watering in coco:
"Volume of Water Needed:
Coco mixed with perlite has the ideal air to water ratio when it is 90%-100% saturated. This means that when the coco has lost 10% of the water that it can hold you should water again. Since water is about half the total volume of saturated coco, the amount of water required should be about 5% of the container volume.
As an example, in 5 gallons of media, it should take about 1 quart of water to achieve adequate run-off. This is less water than most growers assume. Quantities are small because frequency is high. Since you are never giving the coco an opportunity to dry out, there is never going to be much capacity for it to hold more water.
If it takes more than 5% of the container volume to produce run-off, it means that the coco has become too dry. The best remedy is to water more frequently. In coco, it is always better to err on the side of watering too much than not watering enough"
OK - 22 liters is 5.8 gallons, so you're looking at watering about a quart or a little more, each time. Start with a quart measure. If you get runoff, good. If you do not get runoff, then add another watering per day instead of more watering per event. If you barely get runoff with a quart, try adding another cup to see if the runoff is about right then. Realize it may take one big watering or a few small ones to build up the water saturation to the point of getting runoff at all.
Again, have a look at my thread in the coco forum on explosive growth to see what might be coming your way. Or click my profile - I think you can see the images I've posted here already.