I can't tell whether the new tank will breed well or not. My most successful breeding CRS tank is still my 5gal that has given me at least 500 CRS so far. What's not sold so far are in the other 3 20gal now. Each of the tank are holding S, SS and SSS. They all have berried female. I will find out over the next 2-3 months to see how those tank do.
All my new CRS tank uses fluval stratum. I really wanted to use worm castings again but I prefer not to mess with castings is large amount. If these don't work, I'll switch them.
The CRS I recently got from Shawn are 1st, 2nd and 3rd stringer.