Should I remove RO filter or leave it there?

I get water supply from municipal corporation in Ludhiana which is untreated groundwater. The TDS is 275. I use a purifier that has sediment, carbon, RO, UV and UF filter. I want to remove RO filter because the TDS after purification is about 35 and the water becomes acidic. I think TDS of 275 doesn't require RO filter, but I'm concerned about Arsenic and Uranium in water supply. Although I haven't got it tested. Should I remove RO or leave it there? The serviceman suggested that I add a candle to the purifier which contains some stores making water alkaline and also increasing TDS to over 100. I don't know if this will cause stones or any other toxicity or not, although he says that many people have opted for it. What is my best option here? Please suggest.