LC044 -- Use of oxygen multitabs - no chlorine due to skin problem. Refill whirlpool?

I have had the inflatable whirlpool for nine days. So far I have cleaned with oxygen Multitabs, as I don't want to use chlorine under any circumstances. Now I have come across Lotus Clean on the Internet. Now my question: Do I have to refill the whirlpool or can I just add the products to the existing water? I have read that if the water has not been in the whirlpool for more than three weeks, it does not need to be emptied. Is this actually true and can I really start the changeover straight away?

If you have been using active oxygen, you should wait until there is no more active oxygen in the water. This will be after two to three days. Active oxygen and Lotus Clean Shock neutralise each other. You can, however, add Lotus Clean Basic to the water in advance. This is compatible with active oxygen. The three-week rule refers to chlorinated whirlpools. Cyanuric acid and combined chlorine quickly accumulate here. Water that is older than three to four weeks has already accumulated too many pollutants, which is why it makes more sense to empty the whirlpool and start with fresh water without pollutants.

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