Ok Let Me Get This Straight Tank Sizes Question

  1. H

    Holographiccowfish New Member Member

    what are the tank sizes for the following fish

    Fancy goldfish:???
    Guppies and mollies:????
    axolotle i think thats how its spelled:????
    Bettta:??????
    small turtle:??????
     
  2. a

    aced it New Member Member

    Fancy goldfish: 20 g for one, add 10 gallons for each fish after that
    Betta: 2.5 minimum, but they love having more space. One would be thrilled to have 10+ to itself
    I don't know much about the other fish, sorry.
     
  3. emmysjj

    emmysjj Well Known Member Member

    Axolotl - 20 long
    Guppies - 10 gallon
    Mollies - 30 gallon
    @aced it is right about the Goldie’s and bettas.
    No clue on the turtle. What species?
     
  4. Rtessy

    Rtessy Well Known Member Member

    If by small turtle you mean something like a mud turtle, I think 55 is the smallest, maybe a 40 breeder.
    If you mean something like a red eared slider, it's recommended to have 10 gallons per inch of turtle, so you're looking at about 120 gallons.
     
  5. FishGirl38

    FishGirl38 Valued Member Member

    When calculating appropriate tank size for ANY fish. We consider how big they're going to be at full grown size. The tank has to be large enough to accommodate their full grown size and then some to give them space to swim. If you're planning on adding more fish than just the one, than the tank should be that much bigger.

    Fancy goldfish get at least 6-7in long and 4in tall, I would say a minimum of 20G of water will be okay for 1 (A 20G High would be best), If you wanted 4 of them though, than you'd want AT LEAST a 45G tank (55+ being optimal).

    For mollies and guppies who only get about an inch and a half, you could put a small amount (like 3guppies and 3 mollies) into a 10G and they'd be okay. If you wanted more than that then more tank space is required. I wouldn't put them in a tank sized less than 10G though, 5G might be okay for EITHER 1 guppy or 1 molly but...what fun is that?

    The axolotl can get about 8-12in long and would need a minimum of 20G (and a 20G Long is optimal) by itself. You shouldn't have 2 axolotls in the same tank because they can fight/harm one another AND any fish that go in that tank will end up as axi food, so 20G Long minimum is really all there is to an axolotl.

    For a Betta, I'm sure you've heard they live in puddles but 8oz of water is not enough for them, ever. They can go happily in a tank that is 2.5G up to 10G+. The more space for a single betta, the healthier and happier he will be.

    For a turtle, it really does depend on what kind of turtle you have, as you need to account for his full grown size. Typically, I recommend a 40G breeder for turtles. Though we sell red ear sliders and they can outgrow a 40B, turtles need more space than usual fish (because of the dimensions of their shells being so wide and the fact that they need space to swim/enjoy themselves ontop of the fact that they're messy eaters). With the turtle, bigger and wider is always better. The tank should be wider than 20in (a standard 45G is 18in wide).
     
  6. Rtessy

    Rtessy Well Known Member Member

    The minimum for four goldfish is maybe 50 gallons, with many arguing for 60 due to their huge bioload.
    The minimum for mollies is a 30 gallon because of how large they get, and their tendency to overpopulate
    5 gallons is NOT okay for guppies or mollies, but you could house least killifish
    Axolotls do need a minimum of a 20 long, but can be housed together just fine, though 10-20 gallons of floor space should be added for each additional one. 3 can be kept in a 40 breeder.
    For bettas, 2.5 should be the minimum for long finned species while 5 gallons should be the minimum for short finned species such as plakats and females
    Only the smallest of species of turtles would be okay in a 40, most say even that is too small. That would be a single 3-4 inch turtle for that sized tank.
     
  7. FishGirl38

    FishGirl38 Valued Member Member

    These requirements aren't plastered anywhere as an official ruling and we each have different experiences that've shaped the advice that we give. I was going towards the bare minimum with my recommendations, larger tanks are always better.

    But if you're looking at bare minimum, 1 molly (or even 2 male molly) in a 10G tank is fine. Same with guppy, 1 male guppy would do just fine in a 5G tank.
     
  8. Gypsy13

    Gypsy13 Well Known Member Member

    And somebody forgot to tell my female guppies they weren’t supposed to be three and a half inches long. Just sayin.
     
  9. FishGirl38

    FishGirl38 Valued Member Member

    What size tank are they in?
     
  10. IHaveADogToo

    IHaveADogToo Well Known Member Member

    A 20 long is the recommended minimum for 1-2 axolotls. I have 1 in a 20 long by itself, but keeping 2 in this size is acceptable. The confusion on axolotl tanks is because there are people who say 10 gallons is the minimum, but that is for a juvenile axolotl, and it will outgrow that tank. But keep in mind, with axolotls, it's less about how much water the tank has, and it's more about the footprint of the tank. They need a tank that is at least 2 feet wide.

    For bettas, 2.5 gallons was the older American minimum, and 5 gallons is the newer German minimum, and people seem to be overwhelmingly changing their opinion to line up with the German standard. Bettas, like all fish, appreciate space. The more space the better. If you put your betta in a 2.5 gallon tank you might get a few people telling you to upgrade, but nobody is gonna tweet at PETA to publicly shame you like they would if you had a half gallon tank.
     
  11. JLeeM

    JLeeM Well Known Member Member

    Mollies get a LOT bigger than most people think too.
     
  12. Gypsy13

    Gypsy13 Well Known Member Member

    Twenty nine. I’ve just finally separated boys and girls so soon no more fry! Somebody also forgot to tell them to eat their own.
     
  13. Rtessy

    Rtessy Well Known Member Member

    How big do you think Molly's get? You said keeping one in a five gallon is fine, but I think keeping anything over an inch (with active species being excluded) in a five gallon is wrong. No way I'd keep a fish that averages 4 inches in a dinky little five gallon
     
  14. FishGirl38

    FishGirl38 Valued Member Member

    Lol, at least your 29 is large enough to accommodate. I'll admit I've seen some pretty large livebearers, but it's rare to have them get that size. Had that female been housed in a smaller tank, it's likely she wouldn't have gotten that big. Which, you're doing it the RIGHT way by giving her plenty of space to grow. But I've housed multiple guppy in a 5G tank with no problem, it can be done. It's not the best practice, as my 5G guppy will never be as happy/healthy as the 29G guppy is. But it can be done..

    Rtessy, I've seen mollies at about 3.5in. and that's the difference between us and our advice. You're conservative and I agree that your advice is more on point than mine is, what you said is the better way to go about it. I said a molly in a 10G. I might've said 1 molly in a 5G but that's a little much, I agree. But if you're looking at max size and bioload, 1 molly in 5G would work. It's never optimal, that molly alone will get cramped, but it'll work.

    To give context for my bare minimum/less optimal advice...I work at an LFS, the advice I give is based on what I've learned while at the store. (We're about educating people, people come to our store for advice and opinions...we're not your typical fish store) Some people don't think about fish like how we do, and it's hard to get people to listen to you when you're telling them they have to spend 100$ on a (30G long) tank for a fish that is $2.99 (our mollies), it doesn't happen...or rarely are people willing to listen...so the advice I give is based off of the bare minimum that has/will work.
     
  15. Anders247

    Anders247 Fishlore Legend Member

    Fancy goldfish: 40 gallons
    Male guppies: 10 gallons. Females? 20 gallon long.
    Mollies: 29 gallons
    Axolotl: 20 gallon long
    Betta: 5 gallons
    Turtles? I wouldn't keep them in tank, personally. Scratching the glass I would think would be an issue.