Maintenance question

Hi everyone,

Just some quick questions and really hope you can help.

I have a 25g tank that I will be adding coral too at a later stage, it's finished cycling and so far I have added a percula clown, 4 hermits and 4 snails, they are all looking great

I am going to be doing 10g water changes weekly. I have activated carbon, phosguard and filter floss in the filter.

My questions are:
How often do I change the activated carbon?
How often do I have to change the phosguard?
How often do I change the filter floss?
Also is there any other maintenance or replacing other than general stuff such as glass cleaning?

Thanks guys, appreciate the help!