Still not sure what the problem is with my little plant. I wasn't monitoring the nutrient level in my reservoir, so thought it could be over-fertilization. But I checked it last night and the levels seemed to be ok:
... pH=6.49, EC=2100, ppm=1049
Anyway, today I changed the water and scrubbed everything in the res down with detergent and even bleached the pumps and rinsed them thoroughly. Also boiled all of the Hydroton pellets and rinsed them thoroughly. Flushed out the plant's starter plug thoroughly with tap water. Added the nutes & fresh water:
... pH=6.03, EC=2046, ppm=1023
(This is from adding 44 ml Sensi-Grow A, 44 ml Sensi-Grow B, 22 ml B-52, 22 ml Voodoo Juice to 3 gallons H2O. Also added a few ml of "pH UP" to raise the pH level a bit.)
Before cleaning out the res, the water was murky & brown and smelled foul. That couldn't have been good!
Here are some pics from today of my poor plant:
New growth looks okay, but that hasn't been lasting very long. Not very many roots are visible sticking out of the starter plug and overall plant growth seems slow up to now. I hope that my intervention fixes the problem. I'll be monitoring pH & EC daily from now on.
The water in the res is nice and cool, around 70 degrees F or less.
More seeds arrived in the mail this week, so I'm planning to sprout 2 more plants to keep this one company.