Sodium Nitrate is the Dirty Little Secret behind all, and I mean every one of the synthetic fertilizers that really pack a punch. It's the same for figs. The salt forces fluids into the plant cells which then carry with them the nutrients that cause the ((explosive growth)) using synthetic fertilizers. Hopefully pH dialed in neutral fluid solution. That's why those organic fertilizers never pack the same punch. I recommend a balanced combination of both types of fertilizers. Use the organic after initiated explosive growth with the synthetic fertilizer. Without the sodium a synthetic fertilizer just won't work the same. Of course
@Inflorescence JADAM teas work best, but involve a lot of time, and planning. So don't be surprised Joe to see Sodium Nitrate in the fine print of those synthetic hydroponic fertilizers. That's why you get the salt build up when using synthetics. BTW I'm going to build the system like yours. Lettuce is just too expensive in the supermarkets these days. It's insane.