Clean OR Not to clean

First up, apologies for the video quality. The lighting arrangement here didn't really help with the recording. This is my shrimp only 1.2g nano tank. Been running for a few months now with just an air stone & top ups. As u might see in the video clip.. there are close to maybe 50 odd shrimplets in there of diff age & sizes😅 I DID voluntarily try to cultivate the algae (on the glass) so that it can be a good food source for the little critters but.. it's getting out of hand 😅 Now I m hesitant to poke anything in and clean it as I may end up harming the little ones.. Any suggestions? Also, by how many weeks can we make out the grade of a shrimp? I mean how do v know which ones are gonna be deep red & which ones are gonna be almost transparent .. becuz atm almost all look transparent.. some have a slight red in them.