Self-Watering. Top or Bottom Feed Nutrients?

I think this would depend on the style of nutrients you want to feed. Liquid Hydroponics or Dry Amendments, sometimes called "organic feed" if it is dry amendments I would be top watering as it needs that water to carry the nutrients into the medium after they have been broken down by the microbes in the top layer. unless your using compost teas and soaking the amendments in water with a bubblier then its pretty much liquefied all ready and probably would not matter. If you plan on using liquid hydroponics nutrients I feel bottom or top feeding would be fine no real difference IMO, The only issue I see here is this, it would be prone to buildup with no runoff, so it might be beneficial to schedule in a flush every 3-4 weeks to prevent that from happening. Side note, I have not used their growing systems so I could be wrong, but this is how I would look at it. Good Luck!