How to Clean Aquarium Sand Without Sucking It Up

The short answer

Unplug the heater and filter, then wait: Hydor’s support page and Fluval’s E manual give 30 minutes. Swell UK says that, with practice, a gravel vacuum “can be hovered slightly higher above the sand”; Aquarium Co-Op crimps the hose instead. Drain only your planned change, refill with treated, temperature-matched water, and plug back in once full, hands out.

These steps are for freshwater tanks with aquarium sand; reef sand beds are outside this guide. Our guides to changing fish tank water and cleaning a fish tank cover the rest of this routine maintenance task.

What you need

Cleaning tools:

A gravel vacuum or faucet water changer, and a bucket kept for the tank. Aqueon, an aquarium equipment maker: “Don’t use buckets, scrub pads or any other equipment on your aquarium that have been used with soap or other chemicals.”
A water conditioner and a thermometer.
Gloves. The CDC: “Wear gloves when cleaning or caring for your aquarium, especially if you have cuts or wounds on your hands or if you plan to work with rough rocks or spiny fish.” It adds: “People with weakened immune systems should let others in the household care for the fish tank when possible. If this isn’t possible, they should wear gloves.” and “Don’t let children younger than 5 years old clean or handle aquarium items.”
A test kit; our freshwater test kit roundup compares them.

How often, and how deep: the sources differ

Source (type)	How often	How deep
Aquarium Co-Op (retailer)	“about a third” of the substrate per water change	Into the sand, crimping the hose
Dr. Jessie Sanders (aquatic vet)	Not given	Sand 1/4 to 1/3 up the tube
Swell UK (retailer)	“frequently cleaned”	Hover slightly higher
Pisces (sand maker), Galaxy sand	“during water changes”	Not given
Aquariumscience.org (hobby reference site)	Waste on top “on a regular basis”	No weekly “deep vacuum”

Aquariumscience.org differs on deep vacuuming (“We do NOT recommend doing this.”) but says “it is perfectly fine to vacuum the mulm out on a regular basis” when it forms “ON TOP OF THE SUBSTRATE”.

How to clean the sand, step by step

Ready the new water

Aqueon: “Replacement water should be the same temperature as the aquarium water” and “Always treat tap water with a water conditioner to neutralize chlorine and ammonia before adding it to the aquarium.” Dose by the conditioner’s label.

Unplug the heater and filter, then give the heater its maker’s wait

Aqueon’s checklist opens with “Unplug the filter and heater.” Fluval’s AquaClear filter manual: “Always unplug or disconnect all appliances in the aquarium from electricity supply before placing hands in water, before putting on or taking off parts and while the equipment is being installed, maintained or handled.” Two makers give the same wait. Hydor’s support page: “at least 30 minutes before any waterchange”. Fluval’s E heater manual: “If it has to be taken out of the water or when transferring or changing the water, disconnect the heater from the power source and wait for at least 30 minutes to allow it to cool down.” Our reading: where pages differ, take the longer wait, 30 minutes, and never less than your own manual says; with no manual, 30 minutes. Put on gloves (CDC, above, which also says who should not do this job).

Start the siphon

Heater and filter stay unplugged until step 8. Aquarium Co-Op, with the hose end in the bucket and the tube filled underwater: “Raise the tube out of the water and above the aquarium rim until water starts flowing through the hose and into the bucket.” As soon as the water has drained halfway out of the tube, “quickly plunge the tube back into the water”.

Keep sand out of the hose: hover (Swell) or crimp (Co-Op)

Heater and filter stay unplugged until step 8. Swell UK, an aquarium retailer whose guide is by former Practical Fishkeeping editor Jeremy Gay, gives one retailer’s advice: “Being fine, sand can get sucked up and removed by a gravel vacuum, but with practice the vacuum can be hovered slightly higher above the sand and it will be lifted, cleaned and dropped back down.” Co-Op: “Because the substrate is heavier than the fish waste, you can periodically crimp the hose with your other hand that’s not in the water to briefly stop the suction.” Co-Op and Dr. Sanders push into the sand; Dr. Sanders lets it rise only “1/4 to 1/3 of the way up the tube” before pulling up. Our snail guide covers siphoning small snails out.

Decide whether to stir deeper sand; sources disagree about why it matters

Heater and filter stay unplugged until step 8; wear gloves (CDC). Swell suggests you “rake the sand bed with your fingers, turning it over and dislodging dirt and debris”, warns “Fine sand can compact and turn black if not cleaned regularly”, and says “Sandbeds over 2.5cm deep are more prone to compacting and turning anaerobic.” (2.5 cm is about 1 inch.) Modest Fish, a fishkeeping blog: “Stirring the sand bed regularly will mix in oxygen and prevent anaerobic pockets from forming.” Aquariumscience.org says nothing about stirring but disagrees on the reason: “Deep sand beds do NOT do ANY anoxic denitrification nor do they create hydrogen sulfide.” Swell adds: “Wash hands afterwards and arm yourself with a towel to stop drips.”

Stop at your planned amount

Heater and filter stay unplugged until step 8. The water change percentage caps differ. Aqueon’s do’s and don’ts: “Avoid water changes of more than 25% as larger water changes can stress your fish and upset the balance in your aquarium.” Its cleaning checklist calls for “a water change of at least 25% of the aquarium”, so Aqueon’s two pages differ. API, on the beneficial bacteria: “It is not recommended to do more than 30% because it may cause loss of bacteria and be stressful on the fish.” Python: “Do not remove more than one third of the water.” Dr. Sanders: “Do not remove more than 50% of the tank water at a time to avoid sudden swings in temperature and pH.” To stop, Co-Op says to “cover the tube opening with your hand and lift the tube out.” The CDC: “Dump tank water and clean aquarium items in a bathtub, laundry sink, or outside instead of a kitchen sink when possible.” and “Clean and disinfect sinks and bathtubs after using them to dump aquarium water or clean aquarium items.”

Refill slowly

Heater and filter stay unplugged until step 8. Pour slowly or use a smaller vessel; Dr. Sanders says this avoids “a heavy current in your tank that may hurt your fish.”

Plug back in only when the tank is full and your hands and cleaner are out

Hydor: “The Heater can ONLY then be turned back on when the Aquarium is full and the heater is completely submerged.” Fluval: “Do not allow filter pump to run dry.” Dr. Sanders: “Prime your filtration by pouring some tank water into the filter base.” (hang-on-back filters; canister filters vary) If a heater came out of the water while on, Fluval’s E manual says: “If the heater is accidentally removed from water while operating, DO NOT re-submerse it in water. Unplug it and let it cool down for at least 1 hour before reusing.” Then plug both back in; the CDC says to wash your hands “with soap and running water” after cleaning the tank.

With a Python faucet changer, steps 1, 2 and 8 still apply: treat the water, unplug before your hands go in, and plug back in only after the gravel tube is out of the tank (Python’s fill step 6). From the drain step on, in Python’s order: switch OPEN, pump to DRAIN, “Turn on the COLD water”, then insert the gravel tube “straight down to the bottom of the gravel and hold it still”. The sheet is written for gravel and gives no hover height for sand. For gravel itself, see how to clean fish tank gravel. If fish or substrate are drawn up, “you may interrupt the cleaning process by temporarily closing the switch and letting the object drop back to the gravel bed”, and: “CAUTION if your tank has sand, do not force switch to close as this will either score it or break it.” When the tube runs clear, close the switch and move on. To fill: with the tube out, close the switch; set the faucet to the tank’s temperature; turn the pump to FILL; hold the tube over the tank and “slowly turn the switch C to the OPEN position”. Its caution: “DO NOT LEAVE THE SWITCH IN THE CLOSED POSITION FOR MORE THAN THE TIME IT TAKES FOR YOU TO GET TO YOUR AQUARIUM.” Conditioner can go “into the stream of water as you are refilling the tank”. When full, close the switch and remove the gravel tube; only then plug back in (step 8). Follow Python’s sheet for your model.

Powered and hand-pump cleaners: the maker’s steps

Your cleaner’s own sheet has the final word, and sources differ: Swell, a retailer, calls a battery-powered gravel vacuum “Suitable for sand or gravel”, with the device hovered slightly higher for fine sand, while Fluval’s AquaVac+ manual says “Not suitable for fine sand”. Unplug the heater and filter before your hands go in (step 2), and plug back in only once the tank is full and the cleaner is out (step 8).

Fluval AquaVac+ (battery): “It is not recommended to use on aquarium gravel finer than 2mm. Not suitable for fine sand or fine gravel.” Its caution: “CAUTION – Always unplug or disconnect all appliances in the aquarium from electricity supply before placing hands in water or performing aquarium maintenance.” And: “Ensure that the unit is only operated under water so that the impeller does not run dry.”
hygger HG956 hand pump: its sand-washing steps are “Do not touch the sand and gravel.” while placing it, then “Press and absorb the water until the water circulates naturally.”, “Insert the hard tube into the sand to absorb the sand (not too much).”, “Move left and right to clean sand and gravel.” and “Lift up and down to replace sand and gravel.” If sand nears the top of the tube, “lift the hard tube slightly, and the gravel will fall back into the fish tank.” If your filter is powerful, hygger allows returning the outlet hose to the tank; this guide covers its drain method only.

What not to do

No bucket that has held soap or other chemicals (What you need).
No water change before the heater’s wait (step 2).
No hands in with the heater or filter plugged in (steps 2-7).
No heater on before it is fully under water, and no re-submerging one that came out while on (step 8).
No forcing a Python switch closed on sand (Python block).
No cleaner its maker rules out for fine sand (Fluval).
No tank water in the kitchen sink if you can avoid it (step 6).

Ready to buy?

Our aquarium sand roundup compares sands by grain size, pH effect and planted use. More routines: our Tank Setup & Care section.

Frequently Asked Questions

Q. Do you have to rinse sand before adding it?

Yes. Aquariumscience.org: “All sand should be well rinsed before adding it to the aquarium.” Swell: “New sand can turn the water cloudy, so rinse in a bucket for adding it.”

Q. Can you clean sand without a vacuum?

Swell says yes: it rakes the sand by hand, with the heater and filter unplugged until step 8, and says “Combine this with a water change and mechanical filter clean, and dirt will be removed permanently.” Our guide to cleaning a fish tank filter covers the filter.

Q. Does white sand show dirt?

Aquariumscience.org says fish feces “tend to accumulate in a thin, spotty, light to dark brown mulm on the floor of a fine sand bottomed aquarium” that “can be ugly in aquariums with white bottoms”, and: “Gray, tan or brown colored sand can reduce this unsightly problem considerably.”

Q. Will cleaning the sand cloud the water?

Fluval says of its AquaVac+: “When stirring up small dirt particles, it’s normal for the aquarium water to become slightly cloudy. However this cloudiness will quickly be removed by the aquarium filter.”

Sources (18)

Aquarium Tales Team

Written and reviewed by the Aquarium Tales Team. See the About page for how we work.