Emerald crab

Best saltwater fish tank cleaners

Let’s face it, keeping any aquarium clean can be a pain. There is no perfect biological solution that will make your tank completely maintenance-free, but adding a few of the best saltwater fish tank cleaners can help add some interesting dynamics to your tank and lend a helping hand.

Here are the 15 best saltwater fish tank cleaners:

Crabs are some of the best saltwater fish tank cleaners

The reef-safe saltwater crabs have to be at the top of the list when it comes to helping keep your saltwater fish tank clean. These scavengers naturally occupy this important niche and are happy to lend a hand…er…I mean claw in support of keeping things neat and tidy.

Here are three great crabby options and are my favorite of all the best saltwater fish tank cleaners:

Hermit crabs are the most common, inexpensive, and best saltwater fish tank cleaners

You cannot beat hermit crabs, when it comes to helping keep a saltwater aquarium clean and tidy.

red legged hermit crab saltwater fish tank cleaner

These tiny little acrobats will find their way into all the nooks and crannies of your tank or your English muffins, wherever you have nooks and crannies. They eat leftover food, detritus and algae, making them one of the most versatile cleaners on this list.

They are also generally inexpensive. Just don’t buy too many of them, you don’t want them to starve.


Emerald crabs help keep a tank free from algae

This green mithrax emerald crab is a gem, when it comes to fighting hair algae. They are so good at cutting down this problem algae that they can often starve in a tank, once the job is done.

Emerald crab

The image above is of an Emerald crab I added to my tank in 2021 to help tame some hair algae issues I was having. The hair was growing in between the frogspawn heads, making it particularly challenging for me to fight. But the crab took up residence among the branches and dined away to it’s little crabby heart’s content.

Arrow crabs will clean up unwanted invertebrates like bristle worms

Arrow crabs are somehow creepy-looking and cool at the same time. They look like giant water spiders. They’ll spend their days picking food out of the rocks.

arrow crab

Arrow crabs will also help keep the invertebrate population down in your sandbed. If you are not a fan of hitchhiking invertebrates, like bristleworms, then you should consider adding an arrow crab.

Snails will eat algae off glass and other surfaces

Two of the best saltwater fish tank cleaners are Cerith and Trochus snails. They are widely available, relatively inexpensive and great at fitting into those tighter spaces to help keep things clean.

Cerith snails

These tiny, tidy titans are versatile cleaners that will help you keep your saltwater fish tank clean.

cerith snail

Cerith snails are one of my favorite saltwater fish tank cleaners because of the variety of things they will eat, to help keep your tank clean, as well as their small size.

Some of the other mollusks, like the Turbo snail, or the fighting conch grow so large that they actually knock corals and rocks over in your tank.

But the cerith snail packs a lot of cleaning in a tiny package.

Trochus snails

Trochus snails are a close second to the Cerith snails, when it comes to clean-up-crew potential.

Trochus snail

The are a bit larger, which also makes them fun and different to watch. Cerith snails almost seem nimble and agile, whereas trochus snails can sometimes look clumsy. Watching them rasp-away at the aquarium glass can be a bit mesmerizing.


Shrimp are some of the best saltwater fish tank cleaners. They will eat excess foods and even parasites, if you’re lucky.

Peppermint shrimp

The peppermint shrimp is a great cleaner, because they are inexpensive, and they will also help keep aiptasia anemones in line.

Peppermint shrimp

Cleaner shrimp

Cleaner shrimp will eat leftover food and keep your rocks and coral branches free from rotting food and detritus and they also will display an amazing behavior that is even more entertaining than it is beneficial for your fish.

cleaner shrimp


Starfish might be the most controversial choice on this list–because they can sometimes eat something of value in your tank, while they are keeping it clean.

As you can imagine, starfish are great cleaners. They’re like little living roomba vacuums for your tank.

Reef safe starfish

Before you go out and buy a starfish, I do recommend you read this article about reef safe starfish and educate yourself about the pros and cons.

chocolate chip starfish

Sea slugs and Nudibranchs

Berghia nudibranch

The berghia nudibranch is a specialized cleaner that does only one thing. They are great for helping clean up the nasty and dramatically unpopular aiptasia anemone. If you have aiptasia, you can get hours of fun watching them track down and munch on that dreaded hitchhiker.


berghia nudibranch

Unfortunately, they aren’t any good at mowing down majano anemones. So be sure to know the difference before you invest in these crazy-looking creatures.

The dolabella sea hare is another interesting fish tank cleaner choice. I didn’t include them in a prominent way here, because they are a bit more of an expert-level type invertebrate. But they certainly are great at eating algae and keeping your tank clean.


Believe it or not, Macroalgae are actually one of the best saltwater fish tank cleaners. The strategy is a bit like fighting fire with fire.

caulerpa macro to remove nitrates and phosphates from a saltwater aquarium

Fast-growing, nutrient hungry macroalgae, grown strategically in a sump or refugium can help keep your tank clean.

The only caution with macroalgae is that if you’re not careful, they could actually become their own version of a problem algae.

I used to have some caulerpa, like the macro shown in the image above, that grew in my deep sand bed years ago.  It was really hard to finally rid myself of it, once I decided to get rid of it. The stalky body sends out these little shoots that get into crevices and keep popping up new macro shoots.

The hitchhikers: natural saltwater fish tank cleaners that find their way into your aquarium

Some of the absoultely best saltwater fish tank cleaners will find their way into your tank without you even trying. They find their way into your tank on live rock, corals and coral frags and they’re absolutely created, evolved and built for cleaning up unwanted waste.

Bristle worms

They aren’t much to look at, but these gross-looking detrivores do a great job at cleaning up the unwanted stuff that falls to your aquarium floor. Bristle worms also generally do their work overnight, when you’re not awake. They’re like having a cleaning crew for your tank and you don’t even have to pay for them.

giant bristle worm

Stomatella snails

Stomatella snails are another stowaway hitchhiking cleaner that will reproduce in your tank and help keep things clean.

stomatella snail hitchhiker

Pineapple sponges

Having pineapple sponges in your saltwater tank is a sign that you’re doing things right. Sponges are versatile, survival machines. Each cell could potentially create an entirely separate sponge colony somewhere else. But pineapple sponges generally don’t proliferate in your tank unless conditions are strong and stable.

Pineapple sponges

The great part about pineapple sponges is that they are literal biological filters. Their entire way of existing is to suck water in and filter out the particles, cleaning your water in the process.

Saltwater fish

Lawnmower blenny

There are not many saltwater fish that can rival the Lawnmower blenny for their tank-cleaning abilities. As their name implies, they cut down problem algae blooms by constantly grazing.

lawnmower blenny

The pot-bellied blenny in the image above helps keep my aquairum clean. As I mentioned earlier, none of the cleaners in this list will be able to keep your tank completely clean without maintenance, but some of them will go about their days and nights on a relentless pursuit of eating while they clean.

lawnmower blenny was here

The picture above is from my own aquarium–and admittedly–the glass needs a cleaning, but take a look at all those lipstick marks. You can see the mouth imprint of the lawnmower blenny. This fish rasps hundreds of spots completely clear of algae each and every day.

Kole tang

The Kole tang is the iconic, most popular member of the bristletooth tang family. Kole tangs are gorgeous tropical fish and voracious algae-eaters, making them one of the best overall tangs to add to your tank as well as one of the best saltwater fish tank cleaners.

Kole tang

What to read next

I hope you enjoyed this article about the 15 best saltwater fish tank cleaners. Here are a few related articles to help dive deeper on the topics of creating and maintaining a healthy saltwater tank.

23 Interesting clean-up-crew invertebrates that eat algae

The 21 Best algae-eating saltwater fish

The best saltwater fish for a 15-gallon tank


Adding a few saltwater fish tank cleaners to your tank won’t completely replace your need to do some routine maintenance tasks, like cleaning the aquarium glass and performing partial water changes, but they certainly will help you keep things a bit neater, while also adding some amazing, beautiful and interesting natural behaviors to watch.

Many of the animals listed here are beautiful in their own right. The fact that they are also born to chip in and help keep things clean is icing on the cake.

Comments and questions

Do you have any comments or questions about this list? If so, please type it in the comment section below.






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