Freshwater Clean up Crews
Updated: Apr 10
What if you could hire a cleaner just for your fish tank to clean up the leftover food your fish don’t eat, the fish poops, the decaying plants as they die, and they worked for free? All you had to do after that was install a good filtration system (that should already have been done), test the water and change some of the water once a week. Sounds like an amazing deal right? Well, do it then. Introducing Cleanup Crews! Nope, this isn’t a weird offshoot service we’re now offering, this is the 5 invertebrates that you want to get added to your freshwater aquarium.
What is a Cleanup Crew? A cleanup crew is simply an assembly of organisms, be that fish, shrimp, snail or plant that help to control the accumulation of detritus in your tank. Detritus is simply just another word for the waste products that build up in the substrate of your tank. This includes uneaten fish food, fish faeces, and decaying plant matter. A cleanup crew can be composed of various fish and invertebrates that are scavengers, naturally feeding on detritus. Snails are an excellent example of a scavenger that can be used in a cleanup crew – various species of shrimp and crabs also make good additions to the freshwater cleanup crew. Another option, though less effective at mitigating waste, is plants. There are many different options to choose from when it comes to freshwater invertebrates, but some of them are better than others. Here are our picks for the top five invertebrates to consider for your freshwater cleanup crew.
Nerite Snails: While some aquarium snails can become a nuisance, nerite snails are highly beneficial. These snails feed on algae and detritus but they tend to leave aquarium plants alone. Another benefit of nerite snails is that they cannot breed in freshwater so you don’t have to worry about them taking over your tank like some snails do. (Not so) fun fact, typically when snails reproduce they can lay up to 600 eggs in a single batch. Zebra and tiger nerite snails will grow to around 2.5cm, the rest are slightly smaller and will mainly grow to around 2cm so these little guys won’t take up too much space in your tank. Plus, taking care of these snails is easy, so they are a great place to start when you are thinking about adding some invertebrates to your tank to help you keep things as clean as possible. Their lifespan ranges from 1 to 2 years so there isn’t a huge commitment if you decide you don’t like them, and they can reach up to an inch in size when they are fully grown. You should have a minimum of a 5 gallon tank if you are going to add nerite snails to your little ecosystem, though. They’re pretty fond of having rocks and driftwood in their environment, and more surface area means more places to snack on algae.
Mystery snails: A smaller species of Apple snail which are a very popular snail that can be found at almost any local fish store. These snails are true detritivores and will helpfully eat different types of algae, decaying plant matter, and leftover fish food. They only live for around a year, so commitment isn’t a huge issue and they’re easy to care for. They get on well with others and will just slide around nibbling on what they can find. Mystery snails are one of the larger snail species in this article, but they still only top out at around 2in, making them a sure bet for smaller community tanks as well as larger ones.
Amano Shrimp: These freshwater shrimp grow up to 2 inches long and they are known for eating all kinds of algae. Amano shrimp are generally peaceful so they won’t bother your other tank inhabitants, and they may even feed on leftover fish food and other detritus. One thing to be wary of, however, is that large fish might eat these shrimp so keep them with smaller, peaceful species.
Once you get to know these cute little shrimp, which can live anywhere from 2 to 3 years, you won’t find it surprising when you learn that they are one of the most popular types of shrimp among aquarium hobbyists. They follow an omnivorous diet, and they require a minimum of a 10 gallon tank—preferably one that has plenty of live plants. Plus, these little guys will get along well with snails, other shrimp, and fish, so with the right combination of animals, you can easily set up a peaceful little community of varied species.
Cherry Shrimp: These little aquatic rubies are one of the most popular ornamental shrimp species widely available. They’ll grow to around 4cm and they’re pretty hardy if their water conditions are kept stable. A word of warning - they’ll easily breed within the aquarium. Cherry shrimp are great at eating different types of hair algae and will also eat leftover fish food. They come in a variety of colors (though a bright red is the most common) and make beautiful tank mates if kept with smaller fish that won’t hunt them.
Crayfish: Similar in appearance to small lobsters, crayfish can be a colorful and useful addition to the freshwater cleanup crew. Crayfish are scavengers that are likely to eat various types of detritus in the aquarium but they can be territorial with their own species so it is best to keep just one. If you’re thinking about adding crayfish to your tank, it’s important to know that you will need to set up your aquarium so that it will closely resemble the natural habitat of the crayfish; otherwise, they can become stressed out, stop eating, and experience anxiety.
Thankfully, it isn’t hard to get the job done, as you can simply line the bottom of the tank with rocks that they can hide in, along sand that they can burrow into. Your filter, water pump, or air pump should be able to mimic the current of a river. And, because these interesting creatures will eat plants, as well as algae, it’s best to add live plants that are fast growing to your tank. Beyond that, providing your crayfish with the appropriate pellet food will also keep them happy and healthy.
Fiddler Crab: The fiddler crab is a small, peaceful species of crab that generally grows no larger than two inches. These crabs will eat almost anything, though they do require some salt in the tank water in order to survive. These invertebrates are ideal for brackish tanks. They can live anywhere from 2 to 3 years, and they need to live in a tank that is at least 10 gallons in size. The tank also needs to be set up with shallow water, and there should be areas of the environment that rise above the surface of the water as well—these crabs are semi-terrestrial, so they will need to be able to come out of the water as they please. In terms of setting up your aquarium as a community, working with an expert who really knows these animals is recommended. You’ll need to have fish that are not only able to live in a brackish tank, but who can also swim fast enough to get away from a crab that might be aiming to attack. Otherwise, you can maintain a tank that solely houses fiddler crabs.
Freshwater Clam: These invertebrates act as living filters – they help to keep tank water clean by consuming detritus directly from the water column. Freshwater clams only grow about two inches long and they are fairly easy to care for as long as you don’t keep them with fish species that tend to feed on invertebrates (this includes pufferfish). They can also get along well with a variety of snails and shrimp, so you can have an entire cleaning crew to help keep your tank clean. Just bear in mind that they do prefer a pH of 7.0-8.0 or slightly lower, and a water temperature of 70-80°F, if not slightly cooler than that.
Keeping your freshwater aquarium clean can be a challenge since you have to maintain a balance between keeping your water quality high while also making sure your beneficial bacteria have the nutrients they need to thrive. Establishing a cleanup crew made up of freshwater invertebrates is a great way to improve the cleanliness of your tank without adding to your work load. So where do plants come in here? Well it’s not the same as cleaning up poop and moss, and it’s technically not really part of the clean up crew but to give your fish a nicer aquarium to live in then they’re pretty handy. Aside from adding oxygen and removing CO2, as well as their aesthetic benefits and making your fish feel more at home, they’ve got another major benefit: reducing nitrites. Nitrates just should not be in the water of your fish tank. While it is not the number one most harmful substance to fish, it is still not a great thing to have in any tank. Thankfully, there are lots of nitrate consuming plants out there that can help filter your aquarium from this substance. This substance can cause a number of problems that you don’t want to deal with, so it is crucial to nip the problem in the butt before it comes to full fruition. Nitrate removing plants are really important, so let’s go over 3 of the best aquarium plants to reduce nitrates right now.
Duckweed: Without a doubt, duckweed is one of the best plants out there for using up and absorbing nitrates in the water. This is an easily distinguishable floating plant with hundreds of rounded floating leaves. This thing almost looks like tons of miniature Lilly pads all connected together. It’s a good option for a tank that could use some floating plants and for fish that like getting some cover or shade. In terms of using and absorbing nitrates, duckweed is definitely a good choice. It is really fast growing and it multiplies fast, and therefore it tends to eat up a whole lot of ammonia, nitrite, and nitrates too.
You can buy Duckweed here.
What is convenient about duckweed is that it is really easy to grow. As long as the water is fairly clean, it contains some nutrients, and you provide it with some light, duckweed will grow like, well, like weeds. As far as we know, it is one of the best natural water filters out there, plus it looks nice too. Keep in mind that this stuff does grow fairly fast, so one downside might be that you have to trim it often to keep it from overtaking the tank. However, other than that, there are no real problems that you will experience with duckweed, maybe except for the fact that fish tend to eat it sometimes.
Moss Balls: When it comes to looking cool, these moss balls are definitely up there in the popularity charts. In terms of their look, these are little green moss balls that look like mini furry tennis balls. These particular moss balls come with several benefits. First and foremost, they are well known for absorbing, processing, and using nitrates, nitrites, and ammonia in the water. They act as really good natural filters. They are in fact one of the best natural filters for fish tanks out there. We do also like how these moss balls are very low maintenance. They don’t grow very fast, they don’t need all that much light, and they can survive in some pretty harsh conditions. This means that they don’t need much maintenance and there is virtually no chance of them overtaking your fish tank either. They will grow, but not too quickly, which definitely helps make things a bit easier. To be clear, you get 4 of these moss balls in each pack.
You can buy Moss Balls here.
One thing to keep in mind here is that while snails and shrimp might not eat this stuff, larger fish like koi will definitely eat them. This is a drawback that you need to be aware of. Another problem with them is that you might actually need to throw these moss balls out after a few months. They might suffer from the problem of absorbing too many nitrates to the point where they are maxed out. However, we do like the particular Marimo moss balls because they are free of chemicals and pesticides, which is always nice when it comes to putting something in the same tank with your living pet fish.
Water Sprite: Yet another great plant for tank filtration, especially when it comes to removing ammonia, nitrites, and nitrates from a fish tank, water sprite is beautiful, it works well, and is easy to maintain too. Water sprite grows pretty quickly, which is good when it comes to nitrites and nitrates. This is because the faster a plant grows, the more stuff like nitrates it absorbs from a tank.
You can buy Water Sprite here.
While water sprite does require pruning and maintenance to be performed fairly often due to its fast growth, it definitely does a good job at filtering fish tank water. Other than that, water sprite does not require any overly special conditions. It does like fairly well-filtered water, it likes fertilizer, and it does need a fair amount of light. However, these conditions should not be hard to meet as long as you have a decent aquarium setup to begin with. What is also good about water sprite is that as long as there are enough nutrients present in the tank, it can be planted in pretty much any type of substrate. This plant is also referred to as the Indian Water Fern, probably because it originally comes from India and it looks like a cool little fern. It makes for a really nice foreground or midground plant. Many fish and snails do like to eat this stuff, so that is something to watch out for.
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