JBL Algae Magnet Cleaner - L

JBL Algae Magnet Cleaner is a two-part magnetic glass cleaner. One half goes inside the tank, the other stays on the outside, and the magnets hold them together through the pane so you can scrub algae off without putting a hand in the water. JBL rates the range for glass between 6 and 15mm thick.

Key Features

• Works through the glass: no reaching in, no wet sleeves, and nothing dripping on the floor afterwards.
• For 6 to 15mm glass: JBL's figure for the range. The two sizes are not interchangeable, so check which one matches your pane.
• Grip recess on the outer half: a magnet pair this strong needs something to hold on to, or your fingers slide off it.
• Two sizes, M and L: a bigger pad covers more glass per pass but needs more force to move.
• Nothing to assemble: two pieces, no handle to fit and nothing to charge.
• Glass tanks only: a magnet pad is abrasive by design, which is exactly what acrylic cannot take.

Using A Magnet Cleaner Without Scratching The Glass

• Start the inner half near the top and work in overlapping circles downwards, so what you lift does not settle on ground you have already done.
• Stay clear of the substrate. The moment a grain of sand gets under the pad you are grinding it across the glass.
• Lift the inner half off the glass and rinse it if you feel any grit, rather than pushing on.
• Go gently in the corners. The silicone seams are the one part of a tank you cannot repair from the outside.
• Do the glass a day or two before a water change, then siphon the debris out.

Good To Know

• Glass only, never acrylic. A blade, steel wool or a metal-threaded pad will cut straight into an acrylic pane, and the scratches do not polish out in a filled tank.
• The usual way people scratch aquarium glass is to trap a grain of sand under the pad or the blade. Check the face of the tool before each pass and stay a finger's width above the substrate line.
• Strong magnets snap together hard enough to pinch a finger badly and can chip each other. Separate them by sliding rather than pulling, and store them apart.
• Keep magnets away from phones, cards, watches and anything else with a strip or a screen.
• Rinse the tool in plain water after use and let it dry. Never clean anything that goes into a tank with detergent.
• Scraping is the symptom. Algae on the glass means light, nutrients or both are in surplus, so look at the photoperiod, the feeding and the nitrate and phosphate readings as well.
• The inner half of this cleaner sinks if it comes off the glass. If you would rather not go fishing for it, JBL's Floaty range floats instead.