Just sorting by votes might not be enough. Very quickly you’d have a few superstar discussions that will sit on top permanently and keep gaining votes. Sites like Product Hunt work out their “formula” based on combination of factors - votes within a period of time, weight of votes depending on user “reputation” , previous exposure, some boost for fresh-content discovery, etc. We use “Hot” feed for aggregating content using a basic “starter” formula, but you would need to think of your own secret source (And ideally not tell details about it in public forum).