I am not a shopkeeper but do things for my own self or for my home out of interest in my spare time, which you know is hard to find in busy schedule.
Your battery?s backup time has reduced within a year to half and this highlights a bad or dirty electrolyte in batteries right from the first day, maybe on top a bad UPS adjustments.
Treatment at this stage with EPSOM SALT, ups adjustments, battery flush and re-fill with quality electrolyte at this stage may bring your battery back to its useful life but this all requires a lot of time, effort and preparations such as to gather sulfuric acid, de-ionized water, Espom salt, battery chargers etc. only hobbyists out of interest can do all these things and anyone else who will do it for you is going to rip you off badly and maybe at end, you would think, that had you bought new batteries then you would have remained better off. I would advise you to go through this pain yourself or by giving directions to your domestic worker, otherwise this simple piece of technology will remain very expensive and troublesome for you.
The best bet is once you buy a new batteries then take some pain to buy sulfuric acid and de-ionized water separately and ask someone to prepare an electrolyte for you on clean container. This way, you will save yourself from up upcoming trouble of replacing the batteries very frequently and if you can store the equal amount of electrolyte then you can perform a preventive flush after two years, which will be easier then. Plus guaranteed good useful backup time till end maybe 3-3.5 years.
Anyone who will promise to do these simple and time consuming task for you will charge heavily on labor.
