Do you mean you're growing in a net pot? or a solid pot with some holes punched in? You're going to need to punch A LOT of holes in it. Take a look at a picture of a net pot and make sure yours looks like that.
I grow hydro in a bubble bucket. The net pot is very open, so the roots can EASILY grow through and reach down into the water. The water ALWAYS contains a nutrient solution. This way your plant is always feeding. You top off the water/nute solution as the plant drinks it. You want to keep the ph around 5.6-5.8, it will always fluctuate a bit so bump it in the other direction with PH UP or PH DOWN. You will definitely need a ppm meter to ensure you're not overfeeding the plants. Because the plants have direct access to nutes 24/7, when a problem sets in it sets in quickly!
I keep my ppms at 100 per week of age, skipping the first 2.5 weeks. This is total ppm, including my tap water. So at 3 weeks old, total ppm is 300. At 4 weeks old, total ppm is 400, etc, up to 800 ppm at 8 weeks, and I keep it there until the last few weeks when I back off to 600. My tap water ppm is 140, which is a little low and means I need to add a little cal/mag to the nute solution. When I measure what 800 meant in terms of ppms, it was about 1/3 what was recommended on the nute label.
I've never had a problem with slime (I keep those bubblers bubbling!), so I change my res once every 2 weeks until flowering, and then maybe once more. Once the plants start stretching it's really hard for me to manage changing the res, so I don't unless there's a problem. And there usually isn't.
Good luck!
