Coralline algae looks great when it’s covering our rocks, growing on our pumps, and sticking to the back glass of our aquariums. Unfortunately, this fast growing calcium-based algae also grows in place we don’t particularly want it to, such as the front and side panels on our fish tanks. A small purple dot pops up out of nowhere, followed by many more that can get out of hand in a hurry. If you want to keep the front panel of your aquarium clean and fully see-through, scrape those small purple dots off as soon as you see them. By slacking off, you only make the job that much harder, and instead of having to scrape off just a few small dots, the aquarist will have to tackle much larger spots.