Is my tank overstocked?

[20gallontanker]

I have a 20 gallon standard tank and I was wondering if it's over stocked I got alot of ramshorn snails. Some baby mollies around 15 to 20 ,I have 2 adult marbled mollies I have 9 albino corys I also have 3 octocinclus catfish. I use the 15 d filter pads for my tank and I have to clean them every other day .is that because I'm overstocked?

 

[Aiken Drum]

I find snails to be very messy and create a lot of poop, so that may be why your filter pads need frequent cleaning.

How often are you changing water and how much? Do you know what your water parameters are, preferably before your regular water change.

I'm not really a fish breeder, but it seems like a lot of fry for a 20 gallon and would be significantly overstocked when they get to adult size.

Are the 2 mollys breeding? That will cause you long term issues unless you have a plan to deal with the offspring.