" data-description="API pH UP raises pH levels in your aquarium to make water more alkaline. pH is the measure of acidic or alkaline conditions in water. Different fish need different pH levels to be healthy. Test your water regularly to ensure pH levels are correct for your aquarium. This is fast acting, colourless, easy to use and will not cloud your aquarium. Because it is phosphate-free and nitrate-free , it will not encourage algae growth. A useful tool below: