How do I clean a green swimming pool
This is one of the most common questions pool owners ask. And the likely suspect that causes a green swimming pool is, of course, green algae.
Tips for returning your pool from green to blue:
1. If it is green algae, creating a chlorine residual of 3.0 to 5.0 will just about eliminate any algae problem.
2. Make sure your pH is below 8.0.
3. Vacuum the dead algae off the bottom and try to send the material through your “waste” line, if you have one, or use a portable pump that allows you to discharge the waste out of your pool. This way the nitrogen compounds that emanate from the dead algae will not “fertilize” more algae growth.
Check your pool equipment too!
If your water is turbid (cloudy) and green, and chlorine does not do the trick, your filter may be the offending party. A properly performing filter should clear your water within 24 to 48 hours, but sand filters are notorious for recirculating particulate matter.
Floccing agents, especially those that use Aluminum Sulfate (alum) will help, but, changing the filter type to cartridge or diatomaceous earth (D.E.) would be a better solution.
Most filter experts will tell you that particles that are smaller than 50 microns will pass through a sand filter, so you will never remove them. Cartridge and D.E. filters both strain out much smaller particles, keeping your water more sanitary and, of course, much clearer.