How much water?

How far up do i fill my reservoir?

Its 10 gallons, and im using 3'' net pots, and im not sure how far to fill it up, do i fill to the net pot? the bottom? half way? or what?

Fill it up to just below the net pots so the water bubbles just below them. Do this until the roots grow directly into the water. Then you can lower the level a little bit to give the roots more oxygen while still maintaining a 100% humid environment.

Hey Fat. Good answer.
I have a question for you.

I change my rez every week and put fresh water and nutrients in.

Every two days, I notice the water level goes down in the rez and I need to top it off. When I top it off with fresh water the PPM of nutes go down quite a bit. question is: Do I premix water and nutes in a gallon that is at my desired ppm and pour that in to increase the water level and that will maintain my ppm level the same, or do I just add regular water to bring the level up and also lowering the PPM and just know that when I do my water change out, I'll be putting new nutes in?

This is my first time growing. Im catching on fast and have been reading several hours per night trying to learn. Thanks a lot- REP

IF your changing every week then I would just add straight tap with no nutes. Record your PPM drops after you top-off. This tells you how much the plants are uptaking. I initially changed my rez ever4y week but now that I have 50 gallon rezs, that shit gets expensive. I only change out when the amount of plain tap I have topped off with equals the amount of the entire rez...or close to that. Sometimes I'll add a little nutes to raise the PPM levels, but never back to the level when I initially mixed them.

In veg it doesn't matter a whole hell of allot. I am much more careful and swap nutrients sooner when in flower.

The thing about adding nutrients with your top-off is that you don't know which nutrients you should be adding... The plants absorb different nutrients at different times and your meter just reads total salts. So you may see a 200PPM drop and top off with normal strength but maybe those 200 PPM were all macro nutes.. and now you added back micro nutrients.. say Mg, and your micro levels are now soo high they may interfere with or lock out the uptake of other minerals.

Hope this helps.

Legal,

yeah that helped a lot. That was the path I was headed on. Currently my best plant is a Super Lemon HAze, 2nd week in veg. Short stocky, bushy plant. When I did water change at start of week 2, I went 3/4 strength Humbotdt nutes and the ppm was at 1000. The next day the ppm jumped up to 1300 with me not touching a thing and the tips on the plants turned white white white... Just the tips though of the top new growth. So I added some distilled and brought it down to 990ppm. Over the next few days I would add a little distilled water and within a few days the ppm level is down to 500ppm. Thats low to me, but I would like to get those white tips to disappear. Im growing hydro in the largest red folgers coffee plastic container. Due to the long size of my root mass, I only keep 3" of water in the jugs so my roots done drown. Only about 1 quart of water total. Im sure withing 3 water top offs, I have replaced the initial feeding of 1000ppm. Do you recommend anything for me since my rez is only 1 quart or litre of water.lol.... maybe top off with 1/4 strength nutes, or at least start using tap water for trace elements right? the distilled has like a 30 ppm and my tap water comes out at about 300 ppm. Thanks a lot. Let me know.