A preliminary study on the binding and removal of trace concentrations of aluminum ions in waters by two species of algae,Chlorella PyrenoidosaandChlorella Vulgaaris, were investigated. Binding by the former was minimal over all pH ranges, but binding by the latter was effective with a maximum binding of 68% occurring at pH 5. Binding was lowered drastically below pH 2, and this may be used to remove aluminum from the algae. Optimum binding occurred after 20 minutes exposure time of algae to aluminum solution and 450 mg algae mass to 100 mL solution. Binding was reproducible and more efficient in waters with low suspended solids. High salt concentrations interfere with binding, and theChlorella Vulgariscould be reused 7 times with washings between each binding before a noticeable decrease in binding efficiency was found.