Best fish for beginner's 20 gallon tank

December 10, 2010 11:00 PM

Best fish for beginner with no more than 20 gallons of space!

I'm an absolute beginner to fish and I'd like to start an aquarium. Due to apartment living constraints, I think 20 gallons would be about the largest size I would be able to fit. So what kind of wonderful fishies would be happiest in a novice's rather small habitat? I would like to include some aquatic plants as well. Bloodshed is not a feature I prize in pets, so peaceful species are a must. Bonus points for fish that are ok to be left alone for 24-48 hours occasionally. I don't mind intensive cleaning or attention as long as it's on a weekly as opposed to daily basis. Hardiness is an excellent attribute. So who are the raddest to have swimming around in my kitchen? I would also love to hear your recommendations for online resources for fish care. Help me find the perfect swimmy friends!

posted by troublewithwolves to pets & animals (21 answers total)

Tropical (i.e.you have a heater)? Cold water (i.e. you don't)? Marine (I assume not)?

What sort of filtration - undergravel, air-driven box filter, power filter, side-hanger, canister, sump?

The answers to those questions will determine the type of fish, and the best online resources (which in the aquarist world, usually means forums or the occasional site of a really dedicated and outgoing hobbyist).
posted by Pinback at 11:25 PM on December 10, 2010

If you want plants, that tends to put the kybosh on lots of goldfish. I totally don't recommend goldfish in general, they are filthy creatures.

With that size and a planted tank, you would do very well with guppies or other fish in the livebearing family like platy's, swordtails etc. These fish tolerate a wide variety of water environments and temperatures, are relatively easy-going on plants, and best of all are cheap!

You could also consider barbs, danios etc.

Personally, if it were my tank, I would go with the characin family - aka tetras. They are reasonably cheap, never touch plants, and most importantly most of the species get on well with other tank denizens. (I also think they're really beautiful!)

In a tank that size I would get 5 cardinal tetras (much hardier than neons. Avoid neons if you can, they get sick a lot and die), a bristlenose cat for the algae, and maybe some white cloud minnows or other, blockier tetras or a pearl gourami (very hardy and long-lived). You could also pick up some japonic or red cherry shrimp in that size too. They are very cute. That would be a fine start. :) Avoid African cichlids in a tank that size.

For aquariums in general, where else but Age of Aquariums. Excellent resource, friendly forums, good species descriptions, though everybody loves every fish they've ever had nearly, lol.

Aquarium Poetry, and the planted tank will really help you with your plants etc. Aquarium Poetry is a great site, esp if you're having algae troubles. Dusko builds beautiful tanks and I love is dedicated, measured approach to things.

One thing my many years of fish-keeping have taught me is to

1) change the water regularly. Especially on smaller tanks

and

2) pay attention to community dynamics. Stressed fish get sick and die. And fish die all the time without any help, believe me on that one. Some breeds of fish won't play well with others, or some particular fish won't - even though that species generally will . I've had angels in my tank that thought they were little tetras, and tetras that thought they were sharks! Pay attention to the vibe of your tank. A little chasey is fine, but if you have fish that are relentlessly harrassing others, they need to be moved on, or else their presence will exact a heavy toll. I don't waste my time with species with the slightest hint of aggression now, and my tank is healthier and happier for it. I don't think people get this stressed to them enough with fish-keeping. You always hear the "don't overfeed!" and "change the water!" etc etc, but this one factor has done more for the health of my fish than almost anything else.

Good luck, you're about to start and exciting and beautiful hobby! Feel free to memail any questions, but those forums should satisfy your every want.
posted by smoke at 11:27 PM on December 10, 2010 [11 favorites]

Gouramis. Just make sure you get two or three females. A male will muck up your plans.
posted by sanka at 12:16 AM on December 11, 2010

My wife has had a similarly-sized tank for years now and by far the most durable fish has been the tetras. Our rural water is quite variable in quality and many species have pretty strict requirements. Tetras come in a wide variety of colors, shapes and sizes and generally seem to get along well with each other. The gold tetras have been the ultimate champs.

Danios seem pretty hardy as well.

Frankly, for a beginner, I would go with plastic plants to start. Live plants are cool but are another level of effort to keep going well.
posted by maxwelton at 2:18 AM on December 11, 2010

Danios are pretty, but they tend to harass other fish, IME. I loved having black mollies. They weren't too aggressive and were very pretty fish. They also bred like rabbits, I did have to deal with ich fairly often with them, though.
posted by plinth at 3:25 AM on December 11, 2010

When I was two years old, I came wandering out of the living room brushing my hands off on my pants in a satisfied way. "Well," I announced, "I fed the fish!" I'd actually dumped an entire bowl of horrible late-80s potpourri into the tank. All of the fish died, except for my beloved pictus, whom I had rather aptly named Mr. Pictus. Mr. Pictus lived to be quite old, and he looked awesome, too!

I actually know little more about fishkeeping now than I did on that day in 1990, but I recommend a pictus.
posted by easy, lucky, free at 3:31 AM on December 11, 2010 [1 favorite]

Scissortails and Cory catfish have survived the best in my tank. A small herd of corys roaming the bottom of the tank is a major squee.

While livebearers (mollies, platies, guppies, swordtails) are robust, you'll end up with more of them than you know what to do with. Plus, they poop their own weight and have a disturbing (to me) habit of eating their young.
posted by scruss at 4:51 AM on December 11, 2010

I would start off with just one kind of fish first. Then when you are good at not killing then move up to multiple breeds. However, your tank is pretty small and I don't know if I would recommend keeping more than one kind of fish. The general rule is to keep 1 inch of fish per gallon of aquarium. I tend to be on the more conservative side and would recommend no more than 15 fish inches for you. If you get a bunch of small fish, that would mean no more than 15 fish. If you get larger fish, like gouramis, then you could have perhaps 4 or 5.

You might like neon tetras. Live bearing fish, like guppies are cool, as if you have the right conditions, you'll have an ever replenishing supply...

I really recommend this book.

Once you get good at keeping fish, then move to plants. Don't rush into things all at once.

You typically need to feed fish every day. They can be ok if you feed them less, but I might recommend getting an automatic fish feeder if you will be regularly gone for long period of time.

Is there a reputable aquarium dealer in your area? You want to make sure that the fish that you're buying have been well cared for. Typically, places like PetSmart don't do such a good job.
posted by reddot at 5:55 AM on December 11, 2010

Plants make a huge difference to the cleanliness and fish-friendliness of an aquarium. But the main thing for a beginner to bear in mind is that everything happens slowly. What you're really doing is keeping the water. If you can keep the water clean and nitrate-free, which is really a matter of encouraging the bacteria that do the job, then fish will thrive. If not, not.
posted by alloneword at 6:16 AM on December 11, 2010 [1 favorite]

Cory cats are cute and funny, esp. 3-5 of them together. Pygmy gourami are tiny and hard to find -- you'll need to go to a speciality aquarium store, and they may have to order some for you, but they are *wicked* smart for tiny fish. They'll look straight at you and clearly think about you, similar to the way Oscars do, but on a teeny tiny scale. I also recommend a small otocinclus for doing the windows.

Be sure to cycle your tank beforehand (ie, grow yourself a colony of nitrite/nitrate neutralizing bacteria). If you're too impatient for that, I have had luck with using Bio-Spira to instantly cycle; just be sure to buy it at a reputable aquarium shop and make sure it stays refrigerated until you use it. Good luck and have fun!
posted by apparently at 6:45 AM on December 11, 2010

Growing and maintaining a freshwater aquarium with live plants is a bit tougher than buying some plants and sticking them down in the gravel. To do it successfully, you'll likely need special lights, better substrate (gravel) and a means of injecting CO2 into the water. This doesn't have to be expensive, but just something to think about.

The Planted Tank will give you lots of advice.

The good news is that typical "plant-friendly" fish also tend to be good community fish, meaning they'll get along with other nicely.

Be sure to read up on "cycling" first, as this will insure your success, and I'll second what alloneword said above. Think of it as maintaining perfect water, not maintaining perfect fish. Take care of the water, and everything else will be fine.
posted by teriyaki_tornado at 6:57 AM on December 11, 2010 [1 favorite]

Also, see here for some great examples of planted tanks.
posted by teriyaki_tornado at 7:03 AM on December 11, 2010

I have a zebrafish, Maurice, who has been living in a 1 gallon fish bowl for over two years now. He steadfastly refuses to die, even through periods of (unintentional) extreme neglect.

If you're looking for something hardy, go with zebrafish.
posted by phunniemee at 8:57 AM on December 11, 2010

My tank is 10 gallons and for over a year now has happily played host to 2 platys (there were originally two, they had a child - yes, one child, la la la I can't hear you - and then one parent tragically died, leaving me again with two platys) four neon tetras, four barbs, a guppy and an fabulously prehistoric looking algae eater of some kind. The guppies - there were originally four of them too - haven't worked out well: they just disappeared into thin air except for the lone and rather sad survivor but the others are all thriving away. I had a plant but it died so I added a lurid pink plastic plant and all is well. I never change the water. It evaporates quickly and so about every two weeks or so I add another one to two gallons of water combined with Nutrafin Cycle, which I heartily recommend. I also have a heater and of course a filter, a bio-wheel 100 which I do not recommend, as it's never worked the way it is supposed to (i.e., spinning) although since the fish are happy, I guess it is actually working okay.
posted by mygothlaundry at 10:20 AM on December 11, 2010

I agree with pretty much everything smoke says. I have two tanks, one is Bleeding Heart and Buenos Aires tetras, and one is Congo Tetras, two Hoplo Cats and one Synodontis. Tetras are awesome, just don't let the water quality suffer. They like planted tanks. I love the Hoplos, they are fun, active catfish that will surface feed, so they are out and about. They will even let me hand feed them. :) Catfish will dig in gravel though, so make sure you use a smooth pebble substrate and keep your plants weighted.

I have bio-wheel filters along with undergravel filters. Undergravel filters aren't that great for fish by themselves, but they are very good for plant roots, which like oxygen. (I don't worry about CO2 injection, it's really overkill for the average planted tank. It makes plants grow faster, which if you aren't fastidious about cleanliness leads to more decomposing plant material, and can make your tank more acidic. My plants grow at a perfectly reasonable rate already.)

As far as feeding, 24 hours is fine once in awhile. If you're going to be gone longer, I've been quite pleased with the Eheim Feed-Air. I've got four, one for each fish tank and once for each turtle tank. I use them all the time, even when not on vacation, and have been completely satisfied. I think the food gets stale in them, though, so I don't fill the hopper. This wouldn't be an issue if I didn't use them constantly, of course.
posted by oneirodynia at 11:35 AM on December 11, 2010

Will livebearing fish self-regulate? I'm ok with them eating their young, but I'd prefer not to have to fish them out and get rid of some if the tank gets choked with tiny fish.
posted by troublewithwolves at 12:10 PM on December 11, 2010

No. They are the rabbits of the fish world.
posted by smoke at 1:29 PM on December 11, 2010

This may sound strange, but it's easier to begin with a larger tank than a small one. All it takes is one little change to mess up a small tank, whereas that change will be much more easily absorbed by a large tank.

That being said... my first fist was, I believe, a Mollie in a 5 gallon tank. That fish really put up with a lot and it did quite well!

My next tank was a 55 gallon tall-tank. It didn't take up as much space as one of those big long tanks. It was gorgeous to look at. And, as long as I didn't overpopulate it with fish, it was easy to keep. If I'm not mistaken, a 55 gallon tall tank is basically the same size as a 30 gallon, just taller. It was like looking into a picture window with fish! God, I loved that thing.

I'd stay away from any live plants if I were you. What you really want to do is start simple and grow with it over time. Buy a 30 gallon or 55 tall. Get a heater and air filters for it. Start with some basic tropicals. You'll be in heaven!

Best of luck!
posted by 2oh1 at 3:15 PM on December 11, 2010

Seconding a lot of the above advice.

Bigger tanks are easier. Even a 30 gal would be better than a 20 gal and doesn't really take that much more space (water quality is more stable in a larger tank) .

Easiest fish are tetras, danios, barbs (neons are the exception and are pretty fragile). Livebearers are good too. Most will eat their babies given a chance. Unless there are a lot of hiding places (like plants) you won't have a population problem.

Most plants require special care, BUT there are two plants that require almost no effort - Anubias and Crypts. No special bulbs, fertilizer, CO2 or anything. If they start looking weak, just leave the light on for longer. They grow slowly and will never die.

BIGGEST beginner mistake is not cycling the tank. Only start with a few fish, then after a few weeks add more. Throwing in 10 fish at one time is a recipe for disaster.



Also, don't put your tank near direct sunlight or you will have algae problems.
posted by roaring beast at 5:22 PM on December 11, 2010

I have a 10 gallon tank. I have managed to kill an embarrassing amount of fish- we're up to 3 snails and 6 guppies- but I have managed to keep my 2 lovely little African Dwarf frogs alive. They're so much cooler than fish, and they're fun to watch, especially around feeding time when they dart up to the top of the tank and back. I have a pretty minimal tank set up- the basic beginner fish tank from Walmart with an added heater. They get fed once a day and I change out the water in their tank occasionally. When I'll be gone for a few days, I give them an extra pinch of food before I leave. They're a much bigger conversation starter than fish, and they're incredibly peaceful if you want to have fish in the tank with them. Just make sure that you don't get African clawed frogs, they're vicious and will eat your fish.
posted by kro at 11:00 AM on December 12, 2010

Thank you so much for your help everyone! I've been doing lots of reading about many of the suggestions offered and getting mad psyched for aquatic awesomeness!
posted by troublewithwolves at 10:52 PM on December 16, 2010