Nice sized girl I believe

I bought five blue diamond shrimp earlier this year (+ two babies by accident). I now have around 40. My tank is 75L and I have a three guppies, three neon green tetras and four salt and pepper corys.

I test the water every week and do a partial change every other. I have a shrimp die every now and then but overall everyone seems happy.

So, how many shrimp is too many? And what should I do with excess shrimp? Pretty sure I can't sell them on Facebook.

I set up a 5 gallon with 15 cherry shrimp in it, lots of real plants, java moss, frogbit, etc. how much filtration do you think it needs and what is the best filtration system?

I currently have a 2" by 2" sponge filter with an air pump. It seems to be good, but it's a bit loud (anyone know a good quiet air pump?) and is it too much filtration?

Also just random, if anyone knows how to breed ghost shrimp I'm interested if it's any different from breeding neos