This will probably seem like a stupid question to regulars here,
BUT .... here goes .....

I & my wife are complete beginer's at keeping fish.  She was
a couple of goldfish to look after, about a month ago .... & now
the thing has just snowballed from there.   We now have a 4-foot
tank, complete with pumps (at either end) & all the rest of the
aquatic paraphinalia.

 We have around 20 small ( about an inch-&-a-half each, in length)
colwater fish.  Mainly different types of goldfish .... & 3 black moors.

One of the moors is now swimming around with what looks like a
string of white *eggs* (???) attached to it's rear end.  The reason I
say *eggs* (guessing) is that it's belly looks very much swollen,
compared to the other 2 moors.

If they are eggs, should I seperate the moors from the other fish ?

I once heard that goldfish will eat ANYTHING !!   We have an extra,
smaller tank that is kept for emegency / cleaning out the main tank etc...
& an extra pump/filters, if needed.

Or should I just leave the *pregnant* (?) moor with the rest of the fish
& let nature take it's course ?

Any advice would be GREATLY appreciated by 2 ( us ! ) novices !!