Guide
Cleanup crew: the dream team for efficiency
Snails, shrimp, and fish that tackle algae and detritus - and how to combine them for a tidy, balanced tank.
- Core trio: nerite snails + amano shrimp + otocinclus covers algae on glass, surfaces, and plants in most community tanks.
- Tank size matters: otos need groups of at least 4-6; bristlenose plecos need 30+ gallons; shrimp colonies scale naturally.
- They're not a fix: a cleanup crew reduces visible waste - it does not compensate for overfeeding, skipped water changes, or an uncycled tank.
- Match water parameters: neocaridina shrimp prefer harder, higher pH water (7.0-7.8); amanos tolerate a wider range; otos need soft, slightly acidic conditions.
- Avoid the lookalikes: Chinese algae eaters and flying foxes are commonly sold as cleanup fish and are commonly useless or destructive - know what you're buying.
- Stocking order: add cleanup crew after the tank is cycled and stable, not as a shortcut during cycling.
What a cleanup crew actually does
The term "cleanup crew" covers any combination of snails, shrimp, and fish that graze algae, eat detritus, or consume leftover food before it breaks down and spikes your ammonia. They're not magic. They don't replace regular water changes or responsible feeding. What they do is fill niches that your community fish ignore - scraping diatoms off glass, picking biofilm off plant leaves, sifting mulm out of substrate.
A well-chosen crew keeps a tank looking cleaner between maintenance sessions and genuinely reduces the organic load hitting your filter. A badly chosen one gets eaten, breeds out of control, or does nothing useful at all. The difference is matching species to your specific tank - size, parameters, and existing inhabitants.
Snails
Nerite snails
Neritina spp. are the most recommended algae-grazing snails for good reason. They're tireless on glass and hardscape, handling green spot algae and diatoms with no assistance from you. One per 10 gallons is a reasonable starting density; two or three in a 20-gallon tank works well. The main selling point beyond algae control is reproduction: nerites lay small, white, sesame-seed-like eggs in freshwater but those eggs only hatch in brackish conditions. So you get the grazing without the population explosion.
They do need pH above 7.0 and moderate hardness to keep their shells from eroding. In soft, acidic setups (pH below 6.8), shell pitting becomes noticeable within months.
Mystery snails
Pomacea bridgesii are larger - up to golf-ball size - and eat softer algae, leftover food, and decaying plant matter. They won't touch healthy plants, which makes them safe in planted tanks. They lay egg clutches above the waterline, so you can control population by removing the pink, foamy clusters before they hatch. One or two in a community tank is usually enough.
Malaysian trumpet snails
Melanoides tuberculata live in and under the substrate, constantly stirring it, which prevents anaerobic pockets from forming in deep sand beds. They eat detritus and don't bother plants or other inhabitants. The catch: they breed prolifically and populations can reach hundreds in a well-fed tank. Most experienced fishkeepers consider them beneficial; the hobbyist debate is really about aesthetics. If you hate seeing snails crawl up your glass at night, avoid them. If you have a sand substrate and care about substrate health, a small colony earns its place.
MTS populations boom because people overfeed their tanks. If you have a hundred MTS and they bother you, the answer is feeding less - not chemical treatments that will also harm your shrimp.
Shrimp
Amano shrimp
Caridina multidentata are the workhorses of the shrimp world when it comes to algae. They tackle hair algae, thread algae, and film algae that other species ignore. A group of six amanos in a planted 30-gallon tank will visibly reduce a hair algae problem within a week, provided the underlying cause (usually excess light or nutrients) is addressed alongside them. One or two per 5 gallons is a useful density guideline.
They're not invincible. Amanos need stable, mature water - they're sensitive to ammonia and nitrite spikes. Make sure your nitrogen cycle is fully established before adding them. They also won't breed in freshwater, so the population stays fixed unless you buy more.
Neocaridina shrimp (cherry shrimp and variants)
Neocaridina davidi - sold as cherry shrimp, fire red, bloody mary, and several other colour variants - are smaller than amanos and less aggressive algae eaters. Their real value is biofilm grazing. In a planted tank, a colony of 15-20 neocaridina picks over every surface constantly, cleaning up the fine organic layer that builds on plants, wood, and substrate. They also breed readily in freshwater, so a healthy colony sustains itself.
They need pH 7.0-7.8 and moderate hardness (GH 8-15). Soft, acidic water stresses them and causes failed molts. Don't keep them with fish that will eat them - gouramis, bettas, most cichlids, and even large danios will pick off juveniles.
If you want shrimp to survive and breed alongside fish, dense planting is more important than species selection. Shrimp that have Java moss, floating plants, or thick stem plant growth survive far better - juveniles have somewhere to hide.
Algae-eating fish
Otocinclus
Otocinclus spp. are small (3-4 cm / 1.5 inches), peaceful catfish that specialise in soft green algae on plant leaves and glass. They're genuinely excellent at this one job. A group of 4-6 in a 20-gallon planted tank will keep algae on plants visibly in check without disturbing anything else. They're also completely safe with shrimp of all sizes.
The problem with otos is that they're fragile when first bought. Wild-caught otos (most are) arrive stressed and often starved. Many die within the first two weeks. To give them a real chance: buy from a tank that's had them at least a week, choose individuals that are actively grazing (not just hanging stationary), and add them to a mature tank with established biofilm. Supplement with blanched zucchini or cucumber if your algae levels are low.
True Siamese algae eater
Crossocheilus oblongus is genuinely useful for hair algae and brush algae - including black beard algae, which very few other species touch. One is typically enough per tank unless you have a very large setup (200+ litres / 50+ gallons). They grow to 12-14 cm (around 5 inches) and become more territorial as adults, occasionally chasing other bottom dwellers.
The identification problem is real. At least four different species are sold as "Siamese algae eater" and most of them are not C. oblongus. The true SAE has a clean, solid black stripe running all the way to the tail fin, including through the tail. Flying foxes (Epalzeorhynchos kalopterus) have a similar stripe but a distinctly different body shape and are aggressive, territorial adults that eat little algae. Chinese algae eaters (Gyrinocheilus aymonieri) are outright harmful - they attach to the sides of flat-bodied fish like discus and angelfish, scraping their slime coat.
Chinese algae eaters (Gyrinocheilus aymonieri) are sold everywhere and look harmless as juveniles. Adults become aggressive, territorial, and stop eating algae almost entirely. Do not buy one for a community tank.
Bristlenose pleco
Ancistrus spp. are the sensible pleco choice for most hobbyists. They stay under 15 cm (6 inches), eat algae and decaying wood, and leave healthy plants alone. One per tank is standard - males are territorial with each other. Provide a cave or two for hiding and breeding, and supplement with sinking algae wafers or blanched vegetables a couple of times per week. They're hardy, long-lived, and genuinely productive in tanks 75 litres (20 gallons) and up.
Common plecos (Pterygoplichthys spp.) are often sold at the same size as bristlenoses and are not the same thing. They grow to 45-60 cm (18-24 inches), produce enormous amounts of waste, and will destroy planted tanks. If the pleco label doesn't say "bristlenose" or "ancistrus," ask before buying.
Buying a "pleco" to control algae without checking the species. Common plecos grow enormous, eat almost no algae as adults, and produce more waste than a cleanup crew can handle. They're one of the most surrendered fish in the hobby.
Building your dream team by tank size
20-30 gallons, planted community
2-3 nerite snails + 6-8 amano shrimp + 4-6 otocinclus. This combination covers glass, hardscape, plant surfaces, and leftover food with no territorial conflicts. Works well alongside tetras, rasboras, corydoras, and similarly sized peaceful fish. If you're unsure whether your stocking has room for a cleanup crew, run it through the free stocking calculator.
40-75 gallons, planted or semi-planted
3-4 nerites + 10-12 amanos + 4-6 otos + 1 bristlenose pleco. The bristlenose adds coverage on driftwood and larger hardscape while the otos and amanos handle plant surfaces. Mystery snails can replace or supplement nerites if you want something more visible.
Harder setups - cichlid or predator tanks
Most shrimp will be eaten. Nerites are usually safe (shells protect them). A bristlenose pleco works in many cichlid setups if it has hiding spots. Mystery snails can survive in cichlid tanks but may get harassed. Accept that your cleanup options are limited if you keep large or aggressive fish - increase your maintenance frequency instead.
What most guides miss
Cleanup crews are routinely oversold as a solution to algae problems. They're not. Algae grows because of light, nutrients, and CO₂ imbalance - not because you lack snails. A tank overrun with green water or cyanobacteria won't be fixed by adding more amanos. Address the root water parameter issues first.
The other thing guides skip: cleanup crew animals have real bioload. Ten amano shrimp, three nerites, a bristlenose, and six otos in a 75-litre tank are not "free" - they're producing ammonia and consuming oxygen. A heavily stocked cleanup crew in a tank with mediocre filtration can actually make water quality worse. Keep this proportionate.
Finally, some species in your cleanup crew need feeding even if algae levels are high. Otos in a clean, low-algae tank will starve. Bristlenose plecos need supplemental vegetable matter to stay healthy long-term. Don't assume "they'll find their own food" and leave it at that.
App-aquatic lets you log your stocking list and set feeding reminders - useful when you're keeping multiple species with different dietary needs and maintenance schedules.
Track your parameters and get care reminders with App-aquatic.
Get the free appWill a cleanup crew fix my algae problem?
Partially, sometimes. Grazers like nerites and amanos can keep nuisance algae at manageable levels in a balanced tank. But if you have an algae outbreak driven by too much light, excess nutrients, or poor circulation, adding more animals won't solve it - you'll fix the conditions first. A cleanup crew maintains a clean tank; it doesn't recover a neglected one.
Are cherry shrimp or amano shrimp better?
Different jobs. Amanos are significantly more effective at eating hair algae and larger algae types - a single amano outperforms several cherry shrimp in that role. Cherry shrimp are better at grazing biofilm and breeding sustainably in a colony. For pure algae-eating power, amanos win. For a self-sustaining colony that also keeps surfaces clean, neocaridina are the better pick.
Can I keep a cleanup crew with a betta?
Carefully. Nerite snails are generally fine - most bettas ignore them. Mystery snails get their fins nipped occasionally. Amanos are large enough that many bettas leave them alone, but individual fish vary and some will attack anything. Cherry shrimp are usually eaten. Otocinclus are typically safe given their size and speed. Test with snails first, watch closely before adding shrimp, and have a backup plan.
How many otocinclus do I need?
A minimum of 4, ideally 6 or more. Otos are social and do noticeably better in groups - lone individuals tend to hide, eat poorly, and die within months. In a 20-gallon planted tank, 4-6 otos is a reasonable starting group. In a larger, well-planted setup you can scale up to 8-10.
Do I need to feed my cleanup crew?
Yes, often. In a new or very clean tank, otos can starve if biofilm hasn't established. Supplement with blanched zucchini or cucumber slices a few times per week. Bristlenose plecos need sinking wafers and vegetables regardless of algae levels. Amanos and shrimp will scavenge but benefit from occasional shrimp-specific pellets or algae wafers. The assumption that they're entirely self-sufficient gets a lot of cleanup animals killed.