Stevelondon

Hi all. First time post. I have a Bestway Lay-z-spa which I have been using chlorine tablets in. I haven’t used the spa in a few weeks now and the whole thing has been turned off but the cover on. I have just took the lid off to see what the water is like and surprisingly it looked and smelt absolutely fine (by smelt I mean clean and of chlorine) blue water and no signs of green. A few bits of sand or dirt at the bottom but that’s always there. My question is do you think this water would be ok to warm back up and use? Or do I have to drain it and start with another 1000l of water? Thanks