i have a female balloon molly i believe is preggers, there appears to be some sort of slimey looking golden brownish what look like egg sacks

?? at bottom of breeding tank or could it just be poop, but as i say it is very slimey looking not sure what to expect cause never bred b4 !!!! any advice would be great no live fry as yet...............any roughly what size would newly born fry be ... both male and female are marble balloons, i am aware they are livebearers just think i may have some dead ones