On my ZTE Max, leave battery optimiser on or off

[addermc]

In the settings on my ZTE Max phone in battery settings all the apps except 4 or 5 (not optimized,caller ID, voicemail, google carrier svc, google play services, download) or optimized. I'm trying to close apps after I'm out of them, cause I was having storage issues thanks to a SD card getting corrupted. Did factory reset using volume/power buttons. So now I delete each apps cache daily and was told make sure apps are closed completely. They explained it but nothing described is on my phone. Any help would be greatly appreciated Thanks.

 

[Fox Mulder]

Constantly closing apps, whether manually or with an automatic "task killer", and regularly clearing app cache, is not doing your phone any favors. You're far better off leaving it alone and letting Android manage itself which it does quite well. There's plenty of discussion to read about this if you search around.
Hopefully you have replaced the bad SD card and solved that issue. Bear in mind that app data and cache is generally not stored on the external SD but rather in internal phone storage, although depending on your Android version and options provided by the manufacturer there may be an option to move some apps to the SD.
With all that said, if what you have is an original ZTE Max it's getting rather long in the tooth and there isn't much you can do with its limited internal storage and RAM (not to mention the older processor) so it may be time to think about a newer replacement.