Tank mates

Aquarium Breeder is unambiguous: African dwarf frogs will eat all your dwarf shrimp, it is simply inevitable. Our cherry shrimp record is a dwarf shrimp, and its own page is built around breeding a colony. The same source gives amano and ghost shrimp a chance because they can grow up to 2 inches, which is the size of the frog itself.

Tankarium names snails and Japanese algae eater shrimps among the tank mates to avoid, and our amano shrimp record carries Japanese shrimp and algae shrimp among that species’ own common names. Aquariadise refuses invertebrates as a group. The bands overlap from 77 to 78 °F.

Two sources name this animal group as food for that fish. Aquarium Store Depot on the dojo loach: these bottom dwellers feed on invertebrates like snails, crustaceans, and insect larvae, which means that they are not good tank mates for shrimp and snails. The same page addresses this species by name: although larger shrimps like Amanos will probably hold their own against Weather Loaches, I would not recommend taking the risk. The bands meet at a single degree, 72 F.

Named, not inferred. Aquarium Co-Op says to stay away from any fish big enough to eat them and gives three examples: medium to large cichlids, barbs, and goldfish. We hold records for the goldfish and for two cichlids, the angelfish and the oscar, so one sentence in one source refuses three of our own records at once.

Modest Fish singles them out, and in particular, plecos, Aquarium Store Depot says plecos will be very quick to feed on your amazon swords, and Aquarium Care Basics lists them among the rough fish that damage the leaves. Our common pleco record answers from the other side: its own sources describe it taking wood and plant materials, and it runs 72 to 86 °F against this plant at 72 to 82, so the overlap is ten degrees and there is no setting that separates them.

Three of our four aquarium sources name goldfish and one of them is unusually direct: Aquarium Care Basics says a goldfish would pick at it from time to time, and eat the leaves as if it were salad. Modest Fish says to avoid them and Aquarium Store Depot says they will be very quick to feed on your amazon swords. The bands overlap at 72 to 74 °F, our goldfish record running 68 to 74 and this plant 72 to 82, so the pairing is possible in a narrow window and refused on the diet inside it.

Aquarium Care Basics names oscars among the rough fish that damage the leaves and Modest Fish says to avoid them. Our oscar record runs 75 to 80 °F, entirely inside this plant’s 72 to 82, and the mechanism is not appetite so much as size: a ten to twelve inch cichlid in a planted tank rearranges the tank. It is the second plant record here to refuse the oscar, after water wisteria, and both refusals rest on the same two sources.

The same sentence from Aquarium Source, the flowing fins, and here the fish is also slow. An angelfish is a tall, trailing-finned cichlid that feeds in the middle of the tank, and our angelfish record runs 78 to 84 °F against this record’s 72 to 86, so the two overlap across 78 to 82 and the pairing is arithmetically easy. It is the diet row that refuses it, not the water: three of our sources describe this fish taking live prey and decaying scraps as well as algae.

Aquarium Co-Op names angelfish among the fish to avoid in a discus tank, alongside clown loaches and German blue rams. Both are tall bodied Amazonian cichlids and our sources put them in the same size of aquarium, 55 to 75 gallons. The two records also cannot share a heater: the angelfish band is 78 to 84 °F and this one is 85 to 86, so they meet nowhere.

The same source and the same sentence. Everything Fishkeeping names angelfish among the fish to avoid with a flowerhorn. This one is worth printing because the arithmetic does not refuse it: our angelfish record carries 78 to 84 °F, which overlaps this record from 80 to 84, so a grid built only on water would allow a pairing the source rules out. Both are cichlids and both records carry a source calling them aggressive with their own kind.

Not a temperament problem, an arithmetic one. This record carries 78 to 84 °F and the goldfish record carries 68 to 74. Those two bands do not touch, so this is the first pairing on the site that no tank can satisfy at any size.

Named among the fish to avoid on the same list. Our angelfish record carries 4 to 6 inches long and 6 to 8 tall, which is under a fifth of this fish’s length, and the bands overlap at nothing anyway: 78 to 84 °F against 72 to 76 here.

Named, and by the most detailed source on this record. Asked whether assassin snails eat mystery and nerite snails, Aquarium Breeder answers: eventually, yes, and it says larger snails are taken if the assassins gang up. Aquarium Source restricts the prey to snails smaller than themselves, which a 0.5 to 1.5 inch nerite is not always, and AquaticMotiv puts bigger snails on the safe list. So one source refuses the pairing outright and two allow it with a size condition, and the record refuses it: our nerite snail record is the animal a keeper paid a premium for, and one source we cite says it goes eventually. It is the third refusal against that record, after the pea puffer and the clown loach.

Aquarium Breeder names cichlids among the fish that will eat an assassin snail. We hold four cichlid records and this is the one where the water gives no protection at all: our oscar record carries 75 to 80 °F, which is this record’s band exactly. The oscar record also carries a source saying everything smaller is food, on a fish of 10 to 12 inches against a snail of one. Our angelfish record is the same warning with less overlap and is marked a caution; our discus and flowerhorn records are refused by the arithmetic before the diet gets a say.

Named from both sides, which settles a cell the first draft of this record marked a caution. Aquarium Breeder lists pufferfish among the animals that will eat an assassin snail, alongside cichlids, loaches and goldfish. Our pea puffer record carries Seriously Fish asking for small snails with the shell on regularly, which is why that record already refuses our nerite snail. So one source says the puffer eats this snail and our own record says the puffer needs snails: the two statements are the same statement. The bands would have allowed it, since that record runs 74 to 82 °F against 75 to 80 here.

Two sources name assassin snails among the animals to avoid with this one. Aquarium Breeder lists them alongside crayfish, cichlids, loaches and goldfish, and Fish Laboratory lists bettas, tiger barbs, cichlids, crayfish and assassin snails. Our own assassin snail record carries a source saying it hunts snails and does not eat algae, and the bands overlap from 78 to 80 °F. The other record says it too: our assassin snail record carries Aquarium Source restricting its prey to other snails that are smaller than them, naming trumpet, rabbit, ivory and ramshorn snails. Two sources on this record and one on that one, which makes it one of the best sourced refusals on this site.

Named from both sides, which is as clear as a refusal gets here. Aquarium Source names the assassin snail among the predators of this species. Our own assassin snail record carries three sources naming ramshorn snails as prey: Aquarium Breeder lists bladder, ramshorn and Malaysian trumpet snails, Aquarium Source lists trumpet, rabbit, ivory and ramshorn, and AquaticMotiv lists bladder, pond and ramshorn. The temperature bands overlap from 75 to 78 °F, so the water allows exactly what both records refuse.

These are the two records with the lowest temperature ceilings on this site and they do not meet. The axolotl band ends at 64 °F and the goldfish band starts at 68, so the coldest fish we hold is four degrees too warm for this animal. Both are sold as beginner pets in the same shops, and both records carry a source warning that the usual advice will kill them.

Aquarium Co-Op states bettas are notorious for going after shrimp. Our record marks the pairing never rather than risky, and the reason is that the young hatch at about a millimeter.

Named, not inferred. Seriously Fish states that this species is not suitable with small species or slow-moving, long-finned fish, and it names bettas among them. Our betta record carries 2.4 to 2.8 inches and long fins, and this record carries a fish that reaches 12 inches and, per Aquarium Co-Op, should not share a tank with anything small enough to fit in its mouth. The water would have allowed it: the betta band contains 82 °F.

Aquarium Source records that a grown common pleco can target brightly colored fish with flowing fins, and it is hard to name a fish that fits that description better than a betta. Tankarium adds that the temperament changes with age: juveniles are shy and mellow, adults are often aggressive and territorial. The bands do not save it either. This record runs 72 to 86 °F and so does our betta record, so there is no setting that keeps the two apart, and the pleco outweighs a betta by two orders of magnitude when grown.

Named, not inferred. Everything Fishkeeping lists bettas among the animals to keep away from this fish, alongside shrimp, snails, tetras, goldfish, angelfish and rasboras. The water would have allowed it, since our betta record runs 72 to 86 °F and contains this record’s 80 to 86 completely, and the size does not: a 2.4 to 2.8 inch fish with long fins against a 12 to 16 inch cichlid four sources call the most aggressive fish they cover.

The same verdict as our cherry shrimp record and a different reason for it. No source on this record names the betta, but two of them state that ghost shrimp are bought as feeders for larger aggressive fish, and at 1 to 1.5 inches this animal is the same size as the shrimp our betta guide already refuses.

Seriously Fish again, and here the fish is the right size to be food rather than the wrong size to be safe. Our betta record is 2.4 to 2.8 inches and runs 72 to 86 °F, containing this record’s whole band, so there is no setting that separates them. Seriously Fish names the mates it would accept instead and three of them have records here: dwarf Corydoras, Otocinclus and freshwater shrimp, which on this site is our cherry shrimp, amano shrimp and ghost shrimp records.

Both are sold as algae eaters and both records carry a source saying algae alone will not feed them. The otocinclus record has three of four sources asking for a heavily planted tank and 6 or more fish in a 10 gallon; this one has one fish, a cave, a 20 gallon and a source that says it may snack on sword plants. They solve the same problem in a tank of a different size.

Aquarium Store Depot: not good tank mates for shrimp and snails, and although larger shrimps like Amanos will probably hold their own against Weather Loaches, I would not recommend taking the risk. Fish Laboratory also lists shrimp among the animals to avoid. A cherry shrimp is smaller than an amano.

Everything Fishkeeping names shrimp as animals to keep away from this fish, and Aquarium Store Depot lists brine shrimp and krill as food rather than as tank mates. Our cherry shrimp record carries a 30 to 40 mm animal whose young hatch at about a millimeter, and this record carries a fish that two sources feed on fish fillet and feeder fish. The temperature bands overlap from 80 to 86 °F, so nothing but the diet stands between them, and that is enough.

Tankarium names corydoras catfish among the tank mates to avoid, and Aquariadise names other bottom feeders as a group. Both sources also describe an adult latching onto the flanks of other fish to feed on their mucus, and a corydoras is 1 to 3 inches against 5 to 11 here.

Seriously Fish records that this species can display particularly high levels of aggression towards similar-looking fishes, and no two fish on this site look more alike: our siamese algae eater record exists partly to tell them apart, and a federal database lists siamese algae-eater among this species’ own common names. The bands overlap from 77 to 79 °F, so the arithmetic allows exactly the pairing the source warns about.

Refused from our own record rather than from a source on this one. Our oscar record carries a source saying everything smaller is food, on a fish of 10 to 12 inches against 1.4 in here. The water refuses it independently, since that record carries 75 to 80 °F against 68 to 79, meeting only from 75 to 79, and pH 6.0 to 8.0 against 4.0 to 7.0. Nothing on either record names the pairing and the refusal rests on a diet statement we published.

The same sentence and the same source. Seriously Fish names guppies alongside bettas as the slow-moving, long-finned fish this species should not be kept with. Our guppy record carries 2 to 2.5 inches, which is also inside Aquarium Co-Op’s mouth-sized rule, so the refusal holds twice over.

Diet, not temperament, and four of our five sources say it. Aquarium Co-Op: yes, they are more than happy to help with your snail infestation problem. Aquarium Source: Clown Loaches also love to eat snails, and they will eat any freshwater snail they can get ahold of. Seriously Fish records that it preys on aquatic snails. Wikipedia calls it one of the few fishes that will eat bladder snails. Our nerite snail record carries a 0.5 to 1.5 inch animal with a hard shell, and no source we hold says a hard shell is protection from this fish. It is the second refusal against that record, after the pea puffer.

Both sources that name animals to avoid name loaches. Aquarium Breeder puts cichlids, loaches and goldfish in the group that can put a rabbit snail to death in no time. Our clown loach record carries a source calling it a snail eater in its own diet row, and its single published figure, 82 °F, sits inside this record’s band.

Fishkeeping World names loaches among the animals that eat ramshorn snails, and our clown loach record carries four sources saying the same from the other direction, including Aquarium Source saying it will eat any freshwater snail it can get ahold of and Wikipedia calling it one of the few fishes that will eat bladder snails. The water refuses it as well: that record prints a single figure of 82 °F against 70 to 78 here.

One source names this fish among the tank mates to avoid with a redtail catfish, and the reason is arithmetic rather than temperament. Tankora lists oscar, neon tetra, angelfish, corydoras, discus, guppy, goldfish and dwarf gourami as fish not to keep with it, and Seriously Fish says it will not hesitate to gobble any smaller fish. A corydoras is 1 to 3 inches against 47 to 55 here.

Aquarium Store Depot on the dojo loach: not good tank mates for shrimp and snails, and although larger shrimps like Amanos will probably hold their own against Weather Loaches, I would not recommend taking the risk. This shrimp is smaller than an amano. Fish Laboratory lists shrimp among the animals to avoid as well. The bands meet at a single degree, 72 F.

Two sources name snails as food. Aquarium Source: dojo loaches are also known to snack on freshwater aquarium snails and small invertebrates as well. Aquarium Store Depot: these bottom dwellers feed on invertebrates like snails, crustaceans, and insect larvae, which means that they are not good tank mates for shrimp and snails.

The same two sources, and this snail is the one that breeds in the tank rather than out of it. Aquarium Store Depot puts snails on the list of animals a dojo loach feeds on; Aquarium Source names freshwater aquarium snails among its foods.

Seriously Fish will not put this species in a general community aquarium and says to avoid territorial or otherwise aggressive fishes, including most other cichlids. The flowerhorn is the largest cichlid on this site at 9.5 to 16 inches against 1.3 to 2.5 here, and the bands overlap from 84 to 85 °F, so the arithmetic allows a pairing the source refuses.

Two sources name cichlids among the animals to avoid, and this is the largest cichlid on this site at 9.5 to 16 inches. The bands overlap from 80 to 84 °F, so the arithmetic allows a pairing both sources refuse.

Our goldfish record carries Wikipedia stating that because goldfish eat live plants, their presence in a planted aquarium can be problematic. Aquarium Co-Op says goldfish do not eat hornwort and Aquarium Breeder says to keep them apart. This is the first plant on the site that might answer the goldfish record's own open problem, and the sources will not settle it.

Our goldfish record carries Wikipedia stating that because goldfish eat live plants, their presence in a planted aquarium can be problematic, and our hornwort record prints two sources that give opposite answers about whether goldfish eat that plant. On java fern the sources do not split: four of them name goldfish among the animals this plant survives, and one of them says why, that the leaves contain chemicals that taste bad. That makes this the first plant record here that answers a question another record left open.

Refused twice over, which no other pairing on this site manages. Aquarium Source states that small fish like goldfish or guppies will be toast if kept in a tank with oscars, and separately the temperature bands do not touch: this record carries 75 to 80 °F and the goldfish record carries 68 to 74.

Three of our five sources name goldfish among the animals that eat this plant. Modest Fish: goldfish are a big no-no in a tank with water sprite, as they will not hesitate to eat them. Aquarium Store Depot names goldfish, Buenos Aires tetras and some cichlids. Aquarium Breeder names gouramis, goldfish and herbivorous cichlids. That is the third plant record here our goldfish record refuses, after the hornwort and the java fern, and the one with the most sources behind it.

Two of our seven sources name goldfish among the animals that damage this plant. Aquarium Breeder says goldfish consume the leaves and uproot the stems; Aquarium Store Depot says goldfish can uproot or graze it, though water wisteria will persevere. The temperature settles it before the diet does: our goldfish record runs 68 to 74 °F and this plant’s floor is 75, so the pairing has no shared water to argue about.

Named among the fish to avoid on the same source list, for the same reason: a 2 inch fish and a 4 foot predator. Seriously Fish: while it will not hesitate to gobble any smaller fish, it is actually quite peaceful, which is the sentence that makes this a refusal about size rather than about aggression.

Aquarium Breeder names the oscar among three fish that will devour java moss. The same publisher's java fern page names the oscar among the fish that plant withstands, because it finds the hard leaves unappetizing. One source, two plants, opposite verdicts for the same animal, and both are on our oscar record now.

Seriously Fish gives the reason in one clause: this is not a community fish in the general sense, although it is very peaceful, because the males are so small that other fish may eat them. A male here is 0.6 inches. Our oscar record states its diet as a predatory omnivore that eats fish and its adult size as 10 to 12 inches, and the two bands overlap across 75 to 78 °F, so the pairing is arithmetically easy and refused on the arithmetic of the mouth.

The same sentence from Seriously Fish, and the most extreme version of it on this site. Our redtail catfish record runs 47 to 55 inches against this fish at 0.6 to 1.5, and its diet row reads predator. The two records overlap at 75 to 76 °F, which is the whole band this site shares, so nothing in the water separates them. It is the largest and one of the two smallest animals here in the same three degrees.

This is diet rather than temperament. Seriously Fish states the puffer needs small snails with the shell on regularly, and Aquarium Co-Op names live pest snails among what it eats. A nerite is a snail bought to live for one to two years, not a feeder.

Refused from our own record rather than from a source on this one. Our oscar record carries a source saying everything smaller is food, on a fish of 10 to 12 inches, and a platy is 2 to 2.8. The water would have allowed it, since that record carries 75 to 80 °F and this one 70 to 77, so the two meet from 75 to 77. Nothing on either record names the pairing, and the refusal rests on a diet statement we published rather than on an inference.

Aquarium Breeder names oscars among the fish that consume the leaves and uproot the stems, and this is the pairing where that matters, because the two bands are identical. Our oscar record runs 75 to 80 °F and so does this plant, so there is no setting that keeps them apart. The oscar record already refuses one pairing on this site; this is the second, and it is the only refusal here that rests on a fish being large enough to redecorate rather than hungry enough to eat.

The snail record names this fish. FishioHub lists puffers, large loaches and assassin snails as incompatible with rabbit snails, and this record already carries a source putting snails with the shell on in its own diet row. The bands overlap from 78 to 82 °F.

Fishkeeping World names puffers among the animals that eat ramshorn snails. Our pea puffer record carries Seriously Fish asking for small snails with the shell on regularly, which is the other half of the same sentence: a ramshorn at 18 to 25 mm is the small snail that instruction is about. That record already refuses our nerite snail and is cautioned against our assassin snail, and this is the pairing its own diet row was written for.

Not one of our sources publishes aggression as a figure, so nothing here is a number. Territorial appears on the betta record as a word, taken from the source, and a word is all we can honestly print.

The most common true story in this hobby is a betta that ignored everything for two years and then did not. A grid built from species ranges has no way to hold that, and any page claiming otherwise is guessing on your behalf.

Cover changes outcomes and our records say so: cholla wood and moss on the shrimp record, buried time on the kuhli loach. Two pairings with the same band behave differently in a bare tank and a planted one, and the grid cannot see the difference.

Forty eight records is what is verified today, so the grid above is the whole of what this site can answer. Every other pairing you might want is queued rather than hidden, and the queue is at the bottom of this page.