I just sent off for a new board. This one is a mini board for use on tanks that don't require a lot of external connetions.
It has two connectors for DS18B20 temp probes and 3 12 or 24 volt led's (depending on your powersupply voltage). It also has a header for an Adafruit SHT31-d Temp/Humidity sensor(optional) and a header to expose 8 GPIO pins for use with buttons or switches to manually control equipment.
No ATO or Dosing on this board.
I intend to use this board for my sons fresh water tank and my QT tank.
If you want to follow along with the progress of this and the full size board I am working on, check in on my build thread.