So I'm a newb but I've been doing research for a while and picked up a few tips that sound like they'd be useful. Anyone let me know if you've tried these and how they've worked.
2 asprin tablets to a gallon of solution to drop it from 8 to 6. And to raise PH they suggest to use 1 Tablespoon of baking soda into 3 Gallons of solution then wait 10 minutes until rechecking PH.
Pollination can be achieved by shaking the plant at the first sign of blooms, then daily for about three days. Tomatoes need to be pollinated between 11 a.m. and noon for best results. Flowers do like rather high humidity for pollination, so -if need be- mist the plants twice during the time you shake them. Harvest daily and pick off any deformed or damaged fruit.
(from Secrets to a Successful Greenhouse Business by T.M. Taylor)
Using a Multimeter to determine PPM
I haven't tested this, but it makes sense and it would save a lot of money buying a PPM meter.
I E.C. or 1 Siemen = 1 mho/cm of conductivity. To convert E.C. or Siemen to PPM, multiply them by 650. The Mho is the reciprocal of the Ohm of electrical resistance, Mho=1/ohm
Hydroponics people talk about using hydrogen peroxide to add oxygen to your system and kill off harmful bacterial and pathogens. I'd only think about it in a last ditch effort with an aquaponics system since it should also kill of the beneficial bacteria. I also don't know what it would do to fish, so you'd have to isolate the FT while you were doing this.