I have a good question about paying taxes from p - thru entity businesses. Can you help me out ?

You report the income, reported on Schedule K-1 in all the various categories; ordinary income, investment income, capital gains. They all go on your 1040 so losses do offset gains. Losses also offset your other income such as salaries which you report from your companies and any outside employers you have. Portfolio income from the entities is treated as it would be if it was your personal portfolio income. Interest is interest goes on schedule B along with dividends. Capital gains are treated as capital gains. They all go on your return as though they were personal investments.