THANKS ... Yes, it is a 2 in from pump. I was thinking the sewage pump required a 4 in to the stack so was going to tie 2 into a 4 in to stack. So, OK to run grinded poo in a 2 in to stack? A 4x4x2x2 would give me a bit more room for sure.
Thanks in advance for any suggestions.
1) Need to attach sewage pump to stack in basement. Stack elbows out to city about 3-4 feet from joists above.
1) At present there is only a 4x4x2 wye above the elbow (for kitchen sink upstairs).
2) I've added a sewage ejector Liberty 1 hp for new bath...