Ask 'Dr. Spa' Q & A Message Board

: How often should one drain a spa and start up with new water and a new
: mineral filter? My manual states that the water should be good for
: two to three months. The retailer advised that every four months
: would be adequate. From what I have read, draining is done to prevent
: foaming and other things that make the water go bad because of use
: and chemistry issues. The fact is that after four months of moderate
: use and meticulous maintenance, my water looks crystal clear, and the
: PH and other issues are right on the money and locked in. What is the
: recommedation for this scenario? Thanks.

Each situation has the potential to be different with so many factors (frequency of use, contaminants added, amount of chems required, tub filtering capability, source water, etc) that recommendations based on an "average" situation may not apply to you. If the water seems OK to you, it probably is. My water regularly goes 4-6 months. When it starts to show signs of excessive TDS (cloudy when pumps are on and slow to clear after, requires more chems to keep clean) I change it. When you do finally change it, take mental notes on how the water looks/feels before and after. Eventually, you'll be able to say "It's time."

That said... depending on your climate, late fall is a good time to do a change, so that you aren't stuck doing one in Jan/Feb. Also, fresh water is a treat that is cheap enough (in most places) that you shouldn't deny yourself for too long!