Mag-Float 125 (Medium, glass) Review
The floating magnet that wipes algae film off the inside glass from outside the tank in seconds — the daily-driver glass cleaner for any tank with glass up to about 10 mm.
🌍 You'll be sent to Amazon in your country. Indicative price — live, localised pricing coming soon. As an Amazon Associate we earn from qualifying purchases.
👍 Pros
- Cleans the inside glass from outside the tank — hands stay dry, no reaching in
- Floats if the two halves separate, so the inner pad never sinks into the substrate
- Strong neodymium magnet holds firmly through 3/8 in / 10 mm glass
- One-piece, nothing to wear out; the felt pad lasts years of weekly use
👎 Cons
- Pick up grit on the pad and you can scratch the glass — keep it away from the sand line
- The felt pad wipes soft film but will not shift hard, crusty spot algae
- Sized for medium tanks; too weak for very thick glass on large aquariums
The five-second job you will actually do
Algae film on the front glass is the most visible chore in the hobby, and the Mag-Float 125 makes it trivial. The inner half sits inside the tank, the outer half on the glass; drag the outside and the inside pad follows, wiping the film clean. Your hands never get wet and you never reach in. Because it is so quick, it gets done — which is the whole point of good maintenance gear.
The 125 (Medium) is rated for glass up to 3/8 inch (~10 mm), which covers most tanks up to around 470 L / 125 gal. Mag-Float makes a smaller 30 for nanos and a larger 350 for thick-glass big tanks, so match the size to your pane.
The one rule: mind the grit
Every scratch story with a magnet cleaner comes down to a grain of sand caught in the pad. Keep the float away from the substrate line, rinse the pad before use, and lift it cleanly off the glass rather than dragging it down. Do that and it is safe for years.
Where it stops, a scraper starts
The felt pad wipes soft film but will not touch hard, crusty spot algae — for that keep a blade like the Flipper Standard on hand. The magnet is your weekly routine; the scraper is the occasional heavy job. Pair both with a real water change using the Python water changer or an Aqueon gravel vac. More gear on the aquarium maintenance hub; keep nutrients in check with the water testing hub and match your setup on the aquariums page.
The everyday glass cleaner to own. It makes wiping the front pane a five-second job you will actually do, which keeps the tank looking its best — just mind the grit and keep a scraper for hard spots.
Mag-Float 125 (Medium, glass) — frequently asked questions
Magnet cleaner or a scraper — which do I need?
Most weeks you want the magnet. A Mag-Float wipes the soft green film off the glass in seconds with no wet sleeves, so it is the daily driver. Keep a scraper for the occasional hard, crusty spot the felt pad cannot shift — the two are complements, not rivals. The magnet handles the routine; the blade handles the stubborn.
How do I avoid scratching the glass?
Grit is the enemy. Never run the pad down to the sand or gravel line where it can pick up a grain, and give the pad a quick rinse before each use. Lift the inner half straight off the glass when you are done rather than dragging it down into the substrate. Used carefully it is safe on glass for years.
Does keeping the glass clean reduce algae overall?
Wiping glass is cosmetic — the real algae control is nutrient control. A weekly 25–30% water change to keep nitrate down, a sensible 6–8 hour photoperiod and not overfeeding are what actually starve algae. The magnet just keeps the view clear between those changes.
Found your model? Buy it at the right price.
UniverTrack tracks the real price of your aquarium gear across several retailers, spots fake discounts and warns you when it's genuinely the right moment to buy — with an AI assistant to guide you.
More maintenance we recommend
