First Grow Ever😅

So my first grow ever. I fear I don’t know enough but the best way to learn is by doing. I decided on hydroponic because it grows faster and yields more (theoretically) than soil even if it is more complex. Im not sure what sort of yield to expect from my first grow but its more about learning in the beginning so If there are any experienced growers out there I would love some feedback! I made this setup with 4, 25L buckets. Drilled holes for air tubes connected to a manifold and into the air pump. The net pots sit in the lid and the rockwool sits on a small bed of hydroton. The water is about an inch below the bottom of the net pot. So I put 4 seeds into a glass of tap water on a heated mat. 2 days later when they had little roots I put them in the rockwool cube. I left them in a small Tupperware box on the heated mat for another day and made sure the bottom of the cube stayed wet. I moved them into the net pots then in the tent. My equipment is listed above. I have the air pump on 24/7. The light is on 25% about 16” from the top of the pots. It’s on a 18-6 schedule. The fan comes on and off depending on if it gets too hot or humid. Temperature is kept between 22-28 Celsius and humidity 65-75%. I’ve had to put a radiator in the tent with a thermostat to maintain it. So far I’ve managed to keep this atmosphere correct. The water is just tap water with no fertilizers yet. I’ve put ph down to keep it at 5.5-6 and have been checking almost every day. I don’t really understand PPM yet but know it’s a factor. My main concern is that they all seem to be growing at different speeds and I don’t know what to do. Any suggestions would be appreciated. It’s my first grow so go easy on my please😅.