The tank cleaning supplies you need depend on whether you have a glass or acrylic tank, what kind of algae you're dealing with, and the size of your setup. At minimum, you need an algae scraper, a gravel vacuum or siphon, a bucket, and some form of filter media or mechanical filtration. Everything beyond that addresses specific problems like coralline algae buildup, hard water deposits, or stubborn spot algae on decorations.
This guide covers every category of cleaning supply you'll encounter as an aquarium keeper, what each one is actually for, what to avoid (some "cleaning" products will kill your fish), and how to build a practical cleaning kit for any tank size.
Algae Scrapers and Scrubbers
Algae grows on every aquarium glass surface. Removing it regularly, before it builds up into thick mats, is much easier than dealing with established growth.
Glass vs. Acrylic Tanks
This distinction matters more for cleaning than almost anything else. Glass tanks can be scraped with metal blades safely. Acrylic tanks scratch very easily and require plastic-only tools.
For glass tanks, the most effective algae scrapers use stainless steel or carbon steel razor blades. The Flipper Max and Flipper Standard are magnetic scraper systems with replaceable steel blades on one side and felt pads on the other. The magnetic design means you keep one hand dry while the outer magnet pulls the inner scraper across the glass. Replacement blades run $5 to $8 for a pack of 10.
For acrylic tanks, plastic blade scrapers and soft magnetic scrubbers are your only safe options. The Mag-Float Large for Acrylic and the Two Little Fishies Nano MagClean are designed specifically for acrylic. Never use any metal tool on acrylic, and inspect your scrubber pad regularly for sand particles that can become embedded and scratch the surface.
Coralline Algae
Coralline algae (the purple, pink, and red encrusting algae common in reef tanks) is desirable on live rock but annoying on glass. It's harder than green film algae and doesn't respond to soft pads. For coralline on glass, use a sharp blade scraper and work at a steep angle. A basic credit card or hotel key card can do spot work in a pinch.
For coralline on equipment and decorations outside the tank, white vinegar dissolved in a bucket of water (1:10 ratio) breaks down coralline without harming the equipment. Soak for 30 minutes to 1 hour, then scrub with a toothbrush. Never use this inside a running tank.
Gravel Vacuums and Siphons
Gravel vacuums remove waste from the substrate without removing gravel or sand. They're the primary tool for partial water changes in tanks with substrate.
Gravel Vacuums for Substrates
The Python No Spill Clean and Fill is the most commonly recommended gravel vacuum for tanks over 30 gallons because it attaches directly to your faucet, creating a siphon without the bucket-filling step. It works for water changes and vacuuming simultaneously. The tradeoff is that you're adding tap water directly; you need to add dechlorinator in the stream or pre-dose the tank.
For smaller tanks, the Lee's Deluxe Gravel Vacuum and the API Quick-Clean Gravel Cleaner are compact, bulb-start siphons that work well without faucet attachment. These require a bucket.
Sand Substrates
Deep gravel vacuums in sand beds disturb the sandbed too aggressively and pull sand up into the tube. For reef tanks with sand beds, hover the vacuum 1 to 2 inches above the sand surface to pull surface detritus without disturbing the substrate. You'll see a cloud of debris sucked up while the sand falls back down.
For our picks on the tools that make cleaning most efficient, our best fish tank cleaning tools guide compares the main options in each category.
Buckets and Water Containers
The quality of your buckets matters more than you'd expect.
Use only buckets that have never held any cleaning product, soap, or chemical. Even trace amounts of household cleaners are toxic to fish. Dedicate aquarium buckets permanently to aquarium use and mark them clearly.
Two 5-gallon buckets is the practical minimum for any water change routine: one for water removed from the tank, one for prepared replacement water. For saltwater tanks, a third bucket for salt mixing is helpful.
The Brute 10-gallon containers from Rubbermaid are food-grade plastic that won't leach chemicals into saltwater mix. They're available at Home Depot for $15 to $20 and are the standard recommendation for mixing saltwater.
Filter Media and Mechanical Filtration Supplies
Filter maintenance is the most neglected part of tank cleaning. Dirty filter media does more harm than algae on the glass.
Filter Floss and Mechanical Media
Filter floss (also called filter wool or filter batting) is the mechanical filtration layer that catches particulates before they decompose in the water column. Replace it weekly rather than monthly. A dirty, compacted filter floss pad that's weeks old is trapping detritus and leaching ammonia back into the water as it breaks down. Fresh floss for a week is far more effective than old floss for a month.
Bulk filter floss from a fabric store (100% polyester fiberfill, no scent, no treatment) is chemically identical to aquarium-marketed filter floss and costs a fraction of the price. A bag of polyester fiberfill from Walmart or a craft store costs $4 and lasts months.
Sponge Filters and Filter Cleaning
Sponge filter media (biological filtration) should be rinsed, not replaced. Squeeze the sponge in a bucket of tank water (not tap water) to remove trapped debris while preserving the bacterial colony. Tap water chlorine kills the beneficial bacteria in sponge media, destroying your biological filtration.
Rinse sponge media monthly, or more frequently if it's visibly clogged and restricting flow.
Carbon and Other Chemical Media
Activated carbon bags and other chemical media don't need cleaning; they're replaced on schedule (carbon every 4 to 6 weeks). Mechanical media like filter pads get rinsed in tank water or replaced with fresh floss.
Cleaning Supplies for Tank Glass and Acrylic (Outside)
Cleaning the outside glass requires different products than the inside.
For outside glass: any streak-free glass cleaner works, but be careful with spray products near an open tank top. Spray onto the cloth rather than directly on the glass to prevent overspray from entering the tank.
For stubborn mineral deposits (hard water spots) on the outside of glass: diluted white vinegar on a cloth removes calcium carbonate deposits effectively. This is safe to use near an aquarium as long as you don't let it drip into the tank.
Never use Windex or ammonia-based glass cleaners anywhere near an open aquarium. Ammonia is toxic to fish and the fumes from spray cleaners can enter the tank. Commercial products marketed as "aquarium glass cleaners" are typically just purified water with no cleaning agents, useful for streak-free finish but not for removing deposits.
Cleaning Decorations and Equipment Outside the Tank
Decorations (fake plants, ornaments, caves) accumulate algae and detritus over time. The safe cleaning approach:
- Remove decoration and place in a bucket of old tank water
- Scrub with a dedicated (never soaped) toothbrush or bottle brush
- For stubborn buildup: soak in a 1:20 bleach solution for 15 minutes, then rinse thoroughly, then soak in dechlorinated water for 20 minutes to neutralize residual bleach
- Air dry or towel dry before returning to tank
For the bleach soak step, use plain unscented bleach (sodium hypochlorite only, no added cleaners). A few drops of Seachem Prime in the neutralization soak ensures complete dechlorination.
Never bleach biological media (sponges, ceramic rings, live rock).
For complete cleaning equipment recommendations, our best fish tank cleaning equipment guide goes deeper on specific tools for each task.
How Often to Clean Different Parts of the Tank
Building a cleaning schedule prevents any single task from becoming a major project:
Weekly: - Scrape algae from glass interior - Partial water change (10 to 20%), vacuum substrate - Rinse or replace filter floss - Wipe salt creep from rim and exterior glass
Monthly: - Rinse sponge filter media in tank water - Clean protein skimmer cup and neck - Clean powerhead intakes (check for debris buildup) - Inspect heater, thermometer, and any sensors for buildup
Every 2 to 3 months: - Clean decorations as needed - Deep clean sump (remove and rinse mechanical media sections) - Replace carbon media - Check and clean return pump impeller
Annually: - Replace airline tubing (becomes brittle and can kink or crack) - Inspect all pump and powerhead impellers for wear - Consider replacing older heaters (heater thermostats drift over 2 to 3 years)
What Not to Use When Cleaning a Tank
A few common cleaning products will kill fish: - Soap and dish detergent: Even trace residue is lethal to fish and destroys biological filtration - Bleach (inside the tank or on wet surfaces): Only use bleach outside the tank, then neutralize thoroughly before returning anything to the water - Ammonia-based glass cleaners: Toxic to fish; spray fumes can enter an open tank - Scented cleaning products: Fragrance compounds are generally toxic in water - Alcohol-based cleaners: Can strip protective slime coat from fish and kill beneficial bacteria
The rule is: if it wouldn't be safe to eat, assume it's dangerous for your tank until you know otherwise.
FAQ
How do I remove stubborn brown algae (diatoms) from glass? Diatoms are soft and come off with a gentle pass of any soft cleaning pad. They're common in new tanks (first 4 to 8 weeks) and typically resolve on their own as silicate levels drop. If diatoms are persistent in an established tank, check your silicate levels (often high in tap water areas) and consider adding a silicate-removing media to your filter.
Can I use paper towels inside the tank for cleaning? No. Paper towels shed fibers and may contain trace bleach or brightening compounds. Use dedicated aquarium-safe sponges or clean cloth for anything that contacts tank water.
Do I need to remove fish before cleaning? No, and you shouldn't. Removing fish for cleaning is stressful and unnecessary. Clean the glass, vacuum the substrate, and do your water change with the fish in the tank. They'll get out of the way. The exception is if you're doing a full bleach soak of the tank itself for disease treatment or a complete reset.
How do I get rid of calcium deposits inside the tank? White calcium carbonate deposits (common on the waterline of saltwater tanks) respond to diluted white vinegar applied carefully with a cloth. Lower the water level below the deposit line, apply vinegar with a cloth, wait 2 to 3 minutes, and scrub. Rinse the area with clean tank water before refilling. The trace vinegar that enters the water is safe at this level. For heavy calcium buildup inside protein skimmers and pumps, a longer soak in undiluted white vinegar works well.
Building Your Cleaning Kit
For a practical starting kit that handles any tank: - Magnetic algae scraper (Flipper Standard for glass, Mag-Float for acrylic) - Gravel vacuum siphon - Two dedicated 5-gallon buckets - Bulk polyester fiberfill for filter floss - Dedicated toothbrush for decorations - Clean cloth for glass exterior - Seachem Prime for water changes
That covers 90% of routine tank maintenance without unnecessary products or expense.