You can fit up to 12-15 plants under a 400 watt and them do just fine usually. Since you are in a closet or some other area that will limit airflow Id think that you can do 6-8 EASY.
But then there is the issue of that res taking up all the floorspace under the light...
The airstones and airpump in your res may actually add to the speed that your plant grows. In hydro, the more oxygenated the water the faster the growth, and your adding additional oxygen before you actually drip the water onto the roots(which adds oxygen as well)
Its easy to make a setup that would let you hold more plants in the same space, the problem I see is that you go away so often unexpectedly....So it bout near HAS to be able to be automated (self watering)
Some people use drip setups along with soil setups sometimes to make watering an automated process, which could be an option for you if you wanna figure out the timing to it. (never done it myself although I know a couple folks that have)
But yeah well cram some ideas when we get together. 2 stoner brains have to be better than one.
Wow strechette is bulking up a shitload more than I thought. I figured itd happen just thought itd take lots longer.
As for the flushing, That mainly depends on how often nutes have been added to her and how often you have been putting them into her.
I dont think that the taste would be affected that much myself but it depends on the strain as well so I cant say for sure.
I say cut a small hunk of bud that looks the most amber (not necessarily the entire branch unless you just want to), hang it to dry until the stem cracks on it when you bend it and try it out in a glass bowl. It will taste leafy as hell because it hasnt been cured and thats to be expected, However if it makes a "burning" feel in the back/palate of your throat
then it still has a lot of chemical matter in it and should be flushed out still.
Glad to see that all is going well and strechette is in the prime of her (ever so shortening) life.