Is there a way to remove string algae from my pond and rubber liner, without destroying the liner?
String algae are very easy to eliminate, once you know what causes them. String algae are mostly caused by poor filtration and not enough beneficial bacteria in the pond. Too much food is the usual cause of string algae, therefore, stop feeding your fish is the first way to prevent string algae. Removing fish food from the pond means the fish will begin eating string algae, which will quickly remove the problem. After the string algae subside, feed your fish only what they can eat in five minutes.
Next, you need to make sure that your biological system can handle the amount of waste your fish produce. YOU CAN NEVER OVER FILTER! Always use a filter that is sized higher than the manufacturer recommends. A common problem with many filter setups is that too much water flows through the biofilter too quickly, thus minimizing the cleaning capacity of the filter. Beneficial bacteria are all-natural and break down sludge and smells. Professional Koi breeders do at least a 20% water change every week.
Don’t be afraid to learn to use a water test kit. Your water goal is to keep the ammonia, nitrite, and nitrate at their lowest levels.