maintenance

Have a Swiftech H240X closed loop CPU cooler. First installed about a year and a half ago. Am noticing a couple tiny algae growths in reservoir. I only use my system on weekends. When should I do a complete coolant replace? Is it simply at regular time intervals or does it have anything to do...

Anyone dealing with marble - 1. what sealer do you recommend right after installation? - anything else afterwards? 2. What maintenance is needed to keep marble looking good for long? Thanks