need some questions answered

is there a ratio for the air stone vs size of reservoir? like can i have a 2" airstone in a 10 gallon tub ?

can i add ph down to the reservoir while the plants are still in it ?

is there any other way to get thicker stems other than a fan blowing on the plants?

does it make a difference if my light is vertical or horizontal?

1.)More air is better but it really depends on your setup. If you have a flood and drain type system you could get by with less, but with a DWC you want to make sure you have sufficient o2.

2.) I'm not sure, but I don't think it will hurt them, I wouldn't put any directly on the roots.

3.) a Fan is the easiest, you should have a fan for airflow anyways, but you can also lightly tap your plants a few times a day.

4.) YES , there are bulbs made for vertical OR horizontal and I think some universal(both). Make sure you have the correct bulb for what you want to do.

can i add nutes to plants recoverin from ph burns