Hide layers when clustering (Google maps API)?

Question

JavaScript

Hello! I made HTML markers on the Google map - it was necessary to configure their clustering (otherwise there are too many of them). Can you please tell me how to make the layers hide automatically? Because initially clustering is intended for markers, but in my case, ordinary markers are not suitable.

Here is my code: https://jsfiddle.net/8fh05agn/

If it were possible to somehow find out which markers were hidden and which ones appeared, to count their IDs - it would be possible to manually cover id by their identifiers..