thats mad!

hi,
my platy has recently had many, many babies a good thing rite?
well they are growing now and when i changed the filter in my biorb i
noticed a baby fish stuck inside the filter, well, underneath the
bubble tube but, on top of the filter sponge. when i next changed the
filter i took her out and let her free into the water, as soon as i had
put the filter back in place i thaught nothing else of it, the next day
i noticed that she had swam back into the filter,
i couldnt believe it, what will become of this little madam will she
survive or grow too big for the filter and die in there, should i get
her out or just leave her. i imagine she is happy staying there for
such a long time and then trying and succeding to get back

any advice would be much appreciated,
thanks,

Danny