Stocking a 20 gallon tank

[Chrimsomfox]

Hi, Beginner here!
So I recently came into a 20 gallon tank that came stocked (from a family member) with 4 Golden Panda Mollys, 2 Green Cory Cats, and 1 Panda Cory Cat. It's only slightly planted, (with some new offshoots of anubias and 2 medium sized java ferns, that I've placed) and has one decoration (a tree with tunnels).

The tank is currently running a HOB filter (I’m pretty sure it the TopFin Silentstream PF20 PowerFilter that came in a set) and i’ll be adding a sponge filter too)

I'm just trying to determine if this tank would be considered to be overstocked already, or if any other fish could potentially be added to the tank (such as a singular Honey Gourami or such).

With the 1" per gallon rule, i'm pretty sure that the tank is a little small for their full grown sizes, however there's other information stating that different fish could be added based on where they predominantly swim in the tank? I'm just a little confused.

Thank you for any help!

 

[earhtmother]

Www.aqadvisor.com
Not an exact measurment of stocking but better than the old **1" per gallon** rule

 

[Barliman]

AqAdvisor - Intelligent Freshwater Tropical Fish Aquarium Stocking Calculator and Aquarium Tank/Filter Advisor
Not an exact measurment of stocking but better than the old **1" per gallon** rule

It looks like aqadvisor is gone: my saved link doesn't work, and a google search doesn't turn up a new one. In fact, the domain is for sale.

To the original poster's question, I don't think you're overstocked, but mollies can get to a decent size for a 20-gallon tank (long, regular, or tall?). If you're keeping up with your water changes, I should think you could add a few more. In fact, I might trade in one or the other of the corydoras species you have and make a larger school of the other: say, 5-6 green lasers, or 6-8 pandas, which stay smaller.

As for other fish, the mollies are aggressive eaters and might intimidate a shy fish like a honey dwarf. I'd look for something that can compete on even terms for food, such as zebra danios. Also, assuming you have male and female mollies, you'll soon find yourself with fry.

 

[earhtmother]

Barliman
The link in my msg worked for me just now, maybe yours is older???