New tower new seedling in tower watering question..

I have been trying to figure out the perfect timing for watering for a while 

I ran my system for a year or so on 15 min on and 15min off  that worked well for many months but I ended up with some root rot which I was not sure if  the watering was the problem or my other settings

I had some major issues, 22 net pods in only 5 gallon of water , water changes beyond 2-4  weeks  instead of weekly, low power air pump instead of 2w per gallon.  I have fixed all those issues and add some chlorine to my system every 3 days and the water is on continuously now and all is well and even better than before the only issue is too much evaporation but my system is now 12 gallon and I add almost 1 gallon water per day to it.  I have a commercial air pump 20W for 10gallon water with 3 huge airstones 

the only issue with the tower is that I have very strong and hot lights above it so the top netpods can get too hot if the water is off for too long so for me the continuous 24/7 water on is working amazingly well. I know some other tower owners in Florida also run it for 24/7 in summer  and have a cooling system for the reservoir (dont forget soil temp is around 65-68F)

I experimented with 15min on 30min off with not much of problem but only for few days as I was still fighting with recovering from root rot. 

Technically the best setting is 30 seconds on  and 3 minutes off and best way would be sprayers to increase oxygenation of roots. 

as long as your roots are cool , and damp you are golden at nights there is no water intake so as long as they are just dam you are good 

depending on temp, humidity and your custom settings no one can tell you what works the best for you but take comfort in knowing that 24/7 on works if you have good aeration in the reservoir and  you already know that 15 minutes on per hours has worked for you 

beyond that you have to experiment and let us know how that goes.