Tomatoes with black bottoms

[ProZachJ]

In hydro its also variety dependent. For example I've never been able to get Romas to grow in hydro without at least a few fruits having blossom end rot, but have had great success with other varieties. Often times the first truss will experience a problem but then the rest will come out fine. I've found that trying to drive more transpiration in combination with a CalMag foliar spray before the first truss starts to set fruit can help.