Starting out with a more difficult way to grow is a quick road to failure. Potassium is listed as the K number on the nute bottles. Bloom food is where it should be. Feeding issues will never be resolved without proper lighting. Pics 7 & 8 show tall spindly plants with wide internode spacing from lack of light. A plant cannot process the nutes you are feeding it without light.i just recently cleaned the tub out and how would i add potassium?