Hm, I don’t think that brown slime is bacteria. It appears to be brown algae, which is a bunch of microorganisms called diatoms, a type of phytoplankton. The will consume the plant nutrients (not much though), but more importantly they could clog up the pores in the rockwool and they will compete with the root [...]

You could grow a stick. Most leafy greens or herbs would grow slowly in those conditions. I currently have a basil plant by a window I have left with the blinds closed for weeks (I got tired of opening it and I went on vacation as well) and it is still growing, but it [...]

I would be concerned with pathogens, mold, and fungal growth. Also, when you buy worms there are often times other organisms in the soil it comes in, which could include aphids or worse. :-/

The plastics used in window farms are food grade plastics; therefore, they should not leak harmful chemicals under normal environmental conditions. I’m no expert. So, if you know anything in particular please share!

I have a pure hydroponic system. I see no harm in using worm castings in an aquaponics systems. I would just make sure that the organic castings you use are pure or close to pure castings because if it is not it might be high in nitrite or even ammonium that would be bad for [...]

“The Department of Health and Human Services (DHHS) has determined that lead and lead compounds are reasonably anticipated to be human carcinogens and the EPA has determined that lead is a probable human carcinogen. The International Agency for Research on Cancer (IARC) has determined that inorganic lead is probably carcinogenic to humans” http://www.atsdr.cdc.gov/tfacts13.html (ya know, [...]

I would suggest NEVER using bottled bleach to clean out anything that will eventually pass chemicals onto food that you EAT. Sodium hydrochlorite is the active ingredient in household bleach, which in itself is safe to use around plants that yield food for human consumption… the problem is bleach often contains lead and other chemicals [...]