Clams are filter-feeding mollusks that sometimes show up for sale in stores. They are the only critters that may be useful for green water control. They can filter out and eat the single-celled algae that cause green water. Even better, a clam can filter a lot of water fast. But be aware that because clams are filter feeders, they starve in the typical aquarium – the water is just too clean. Hobbyists should not buy clams unless they want to try them to solve a green water problem. In particular, do not buy clams for their looks because the first thing they do is bury themselves in the gravel. You will likely never see your clam again, even after the green water clears.
I hoped I’ve steered you toward the right choices for controlling whatever type of algae is in your aquarium. Hopefully, algae will no longer be a problem for you. Happy fishkeeping!
How to Control Aquarium Algae - The Spruce
Some fast-growing plants produce chemicals that suppress the growth of algae. The details are still unclear, but planted aquariums with healthy, fast-growing plants tend not to have major algae problems. The most common algae in such freshwater tanks are green algae, and these are easily managed by adding some small algae-eating fish or invertebrates, such as Crossocheilus siamensis, nerite snails or Amano shrimp.
algae growth is unsightly and can be hazardous to fish and plants
A variety of topical fish, snails and shrimp are sold as algae-eaters for the freshwater aquarium. Most of these and invertebrates only eat green algae, ignoring blue-green algae completely and having a marginal effect at best on red algae and diatoms.
Causes and Fixes for Yellow or Brown Aquarium Water - The Spruce