Maintenance of inverter batteries:
Inverter batteries are deep cycle AGM or GEL batteries.
These batteries are room temperature batteries. Therefore to increase the life span of your batteries you must.....
1.Ensure its below ROOM TEMPERATURE
2.Ensure the batteries terminals is tight
3.Ensure the batteries are well ventilated
4. Don't over load your battery
There are different types of deep cycle batteries * 100 AH. 150AH, and 200AH
For a load current of 10 amperes (A)
100AH will last 10 hours while 150 AH will last 15 hours and 200AH will last 20 hours....

what capacity of charger is good for 200ah battery

Any inverter with mains of >= 200V can charge 200 AH batteries connected in series or parallel. If your mains is low, you need a stabilizer