How to Clean Fish Tank Gravel in 5 Quick Step (Vacuum or Not)

By Jecinta Mwihaki @aquariawise

How to Clean Fish Tank Gravel in 5 Quick Step (Vacuum or Not)

Dirty substrates are a momentous cause of poor water quality in many fish tanks. Gravel harbor food residue, rotting plants and fish waste trapped between pebbles which increasingly make the water toxic; sometimes even creating a pungent stench.

Though regular water changes will expel the toxic waste, dirty gravel will toxify the new water quite fast. Therefore, it’s imperative to clean your gravel regularly, together with your glass surfaces and decoration.

The best way to clean gravel in a fish tank is using a gravel vacuum cleaner. Place the hose end of the gravel cleaners in a bucket and completely submerge the tube (cup) end inside the fish tank. Get the water flowing through the vacuum kit, then push the tube opening on the subtrate to siphon dirt from your aquarium gravel.

You should clean the gravel in your fish tank using a recommended gravel vacuum cleaner as often as once every week (or biweekly). The gravel vacuum cleaner is the best way to clean fish tank gravel by hand.

See details on how to properly clean aquarium gravel both with or without a vacuum cleaner.

Plus take a look at how often you should change your fish tank gravel.

But first.

Do You Really Have to Wash Aquarium Gravel

With a fully cycled tank, you should have a stable amount of beneficial bacteria to breakdown fish waste ammonia and nitrites at an efficient rate.

Which means it virtually possible to maintain a fish tank without too much gravel cleaning.

The least you should do is vacuum solid food and plant grime from your substrate.

Nonetheless, complete failure to clean your gravel will gradually culminate to your water getting dirty more quickly meaning frequent water changes.

As well, algae will thrive in dirty gravel accompanied by a rotten egg odor from excess anaerobic bacteria bloom in tiny oxygen-free pockets between compact pebble.

So, vacuum your gravel not only to remove dirt but also, to break these pockets forming within compact gravel. Alternatively, use airstones to improve water movement within the substrate.

How Often Should You Clean Fish Tank Gravel

How often you’ll clean your gravel will depend a lot on the dynamics of your fish tank.

Generally, dirt accumulates faster in smaller, plant less and overstocked aquariums. In which case, you should do thorough gravel cleaning every two weeks.

Moreover, try to change 10 to 20 percent of the water weekly.

If you have a densely planted tank, you may forego the biweekly gravel vacuuming, and instead, do it once every month. However, ensure dead plant leaves that decompose on gravel are not part of the problem.

Gravel in overstocked aquariums will accumulate dirty quickly meted out by food waste from feeding more fish. This especially if you have wasteful fish or species that produce a lot of waste like goldfish and Oscars.

Put simply, a light biweekly gravel vacuuming is necessary, unless you have a fairly clean tank, then you can wash your substrate once every month.

How to Clean Aquarium Gravel — Step by Step Guides

Given your situation, there are a couple of ways you can wash your aquarium gravel. The path you take will mostly depend on the situation, type, and extent of dirt on your substrate.

Below are several ways you can clean dirty gravel.

How to Clean Fish Tank Gravel with a Vacuum Kit

A siphon vacuum gravel cleaner is used to vacuum aquarium gravel. It works by using gravity and hydrostatic pressure to suck dirt from substrates and help dispose of outside the tank.

To use a siphon vac kit effectively, ensure

Vacuuming Your Gravel in 10 Quick Step

Let’s start.

Step 1 — Unplug

Unplug your heater, filter, and air pump but leave your tank decorations, plants, and fish in the aquarium. Generally, the process should be fairly quick and should not stress your fish too much.

Step 2 — Submerge

Get your aquarium gravel vacuum cleaning kit and the old water bucket. Place the bucket below the aquarium level then start the vacuum process by submerging the kit in your tank. Make sure the siphon vac tube is wholly inside the tank.

Step 3 — Up-Down Motion

Start moving the tube inside the water in small up-down motions about 2 to 4 inches above the gravel until water starts flowing through the tube into the bucket below.

Step 4 — Vacuuming

Once you’ve established a flow, move the tube over the whole gravel surface making sure you get all the grime.

For a more complete clean on your tank, simply move the gravel vac further into the substrate itself. The tube might suck in a few pebbles, but they should fall back once you raise the tube.

Step 5 — Turn the Tube

Once the water level has dropped to around 25 to 30 percent of the water removed, meaning your tank is about 75 percent full, simply turn your gravel vac tube up while still inside the water, Take it from the tank and let it drain out through the tubing.

The tube might fill up before you get to the desired water level, just empty the gravel vac and continue the vacuuming till you reach the desired level.

Step 6 — Plug Back

When you are confident the gravel is reasonably clean, clear the cleaning area then put your heater, filter and air pump back in the tank.

How to Clean Fish Tank Gravel without a Vacuum Kit

To clean fish tank gravel without a vacuum, move your fish to a cycled spare tank, the use a siphon to empty 50 percent of your fish tank water. Remove heaters and decoration, then use a bucket to scoop out the dirty gravel from the tank. Place the gravel in a sieve and run clean water through, then let the gravel sit in a bucket with 2 to 4 cups vinegar solution for 2 hours before putting them back.

That said, note that cleaning fish tank gravel without a vacuum is not easy, plus it takes more time and effort and there are a few cons associated with this method.

First, you’ll need to move your fish to another tank and pour out the gravel, which is quite stressful and will disrupt useful bacteria that have established in your tank.

You will also need a big, clear space and time to hack it.

However, cleaning fish tank gravel outside the tank without a vacuum will help you break lumped dirt pockets that a vacuum can’t reach.

To clean your tank without a vacuum, follow these steps.

Step 1 — Prepare New Tank

Prepare a clean tank where you’ll move your fish while you clean the gravel. Then use a siphon or a cup to move about 50 percent of your tank water to the holding tank.

This should ensure your fish are held in the same conditions they are used to.

Step 2 — Transfer Your Fish

Transfer your fish into the new tank using a net. However, if you keep fish that have flowy fins like bettas, you may need to use your hand to move them. Flowy fins and tails easily get tangled up in the net threading and could hurt the fish.

Step 3 — Unplug

Remove your heater, filter and air pump from the tank.

Unlike when using a gravel vac kit, here you’ll also need to remove your plants and decorations plus unplug electrical equipment like aquarium lights.

Step 4 — Clean Your Gravel

In this step, there are two ways you can go about it.

First you can use a cup or a fairly sized container to take the dirty gravel out and place it in a sieve for cleaning.

Or if your aquarium is not too heavy, take the remaining water level dow enough then slowly pour the gravel into a holding pan.

Rinse the dirty gravel in your sieve with running water or use a hose to do the washing.

If you have your gravel in a holding pan, fill it with water and use your hands to move the gravel around. Tip the pan slightly while shielding the gravel with your hand to pour out the dirty water then rinse the gravel.

Either way, make sure you don’t clean all the gravel. The portion that remains uncleaned will help keep nitrifying bacteria which will then recolonize your tank once it’s re-established.

Step 5 — Plug Back and Refill

Once the gravel is clean and dry mix it with the portion let unclean then put it back into your tank. Add your equipment and decoration then plug back electrical equipment.

Prepare clean water set in the perfect conditions for your fish tank and refill it making sure the water is at the correct temperature and ph.

Step 6 — Put the Fish Back

Add your fish back to the tank in the same way you moved them.

How to Get Rid of Algae in Fish Tank Gravel

Sometimes you will have algae in your substrate that may or may not appear in other tank surfaces. This alga is called substrate algae.

The algae start as patches on gravel then spread to other parts of your tank. Luckily removing brown algae ( learn more in this article) from your gravel is fairly easy.

To get rid of algae in fish tank gravel, use an siphon cleaner to vacuum your gravel. You can also kill algae on fish tank gravel naturally by cutting off the food source, such as light, nitrate and phosphate, and introducing algae eating fish, like suckermouth and otoninclus cat fish.

Alternatively, stock algae eaters like suckermouth catfish and they’ll gladly sort your problem.

How Often to Vacuum Gravel in Fish Tank

You should vacuum gravel in a fish tank as often as once every week (weekly), but you can vacuum every other week if your fish are not messy feeders. You should not have gravel vac with every water change, but with every second and thrid change is advisable.

If you don’t gravel vac you substrate often (as stated), dirt will accumulate on the gravel causing a spike in ammonia and kill your fish.

Luckily, you should not have to remove your fish from the tank while vacuuming gravel.

That’s all for this post.

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