Bubbleponics - O.K.C.

Notes from 6/8/2024: The third seedling never popped, and I tossed it on Thursday 6/6.  The two seedlings, as of 1030, both have tap roots at ~ 2" long coming out the bottom of the cubes.   I am starting the system today.  My two primary concerns: The water spells perfume.  I have left that water in the container since mid-April (~ 2 months give or take).  I hope it doesn't cause any problems My water level indicator is a stainless steel rod.  Supposedly it's pretty hardcore, but it will be submersed in a salty solution for several months at a time.  I hope it wasn't a bad idea.  One thought I had was to coat the metal with a silicone of some kind, but right now it's a bit too late for that. (Checked on the net, and it looks like sprays intended for things like high-heat are silicone based spray-paints.  This is most likely the best option for me to maintain the rod.  Maybe I should buy an new rod, paint it, and swap it out based on how this one performs.)  From what I've read it shouldn't rust, but get pitted instead. Installed carbon filter removed humidifier due to lack of receptacles   Jack's 321 quarter strength HydroGuard 30ml Started at 6.2 ph oAdded 7 drops down Brought it down to 6.0 ph oAdded 7 more drops of down Still stayed at 6.0 ph oAdded 15 more drops of down Got it to 5.8 ph EC @ 0.4/0.5 Finished up everything by 1200