2.5 Gallon Fish Tank Pros and Cons: Should You Buy a 2.5 Gallon Fish Tank?

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[talulahrose]

There was 99 comments so I wanted to make it 100

[timrussell]

My betta lives in a 2.5 gallon on our night stand. He does very well in it, active and healthy. The downside I see to it is it can be difficult to find a heater and filter that fits the tank without taking up a lot of room. I ended up going with a mini sponge filter and a tetra preset heater. No complaints and like you said, I do water changes with a gallon pitcher and a mini syphon. Only takes a few minutes but I do water changes way more frequently and in larger volume than the rest of my tanks to ensure the smaller body of water stays clean.

[rhyanlumilay]

Actually it all depends on the keeper. One might have budget for a larger tank but there are people who doesn't have, there are people who has a big space to put a larger tank but some only have small space to accommodate, some people wants to have tons of fish but some just like to have a single pet. So there are several instances to consider why a fish keeper wants a 2.5g and are frequently make fun by those who have larger tanks.

[BertShackleford]

Nano tanks are my specialty. They do require a fastidious amount of maintenance. You simply do not have the luxury of being lazy and skipping a day. Meticulous attention to detail is an absolute requirement. Don't expect to go on any extended trips for more than 48 hours either or you _will_ return home to some sort of problem (usually just an algae bloom if you're lucky).

When choosing plants for nano tanks, make sure they are the appropriate size. Nothing with large stems or leaf structures. You want to look for plants that are tiny-very small. Plants such as Anubias nana 'petite', any _Bucephalandra, _ Crypt parva/lucens/lutea (in order from smallest to largest - I wouldn't recommend going any bigger), Giant Baby Tears _Micranthemum umbrosum_ is a good stem plant and adds some bright green color, Dwarf Water Lettuce for floaters, Scarlet Temple for some red color and other various plants considered to be tiny/very small. Pygmy Chain Sword _(Helanthium tenellum 'green')_ and _Marsilea hirsuta_ seem to be the only two carpeting plants that work in our nano tanks. All of these plants thrive well in our tanks without the use of CO2.

To simplify - when looking for nano tank plants you generally want to search for species that stay under 10-12 inches in height. That's usually a safe guideline when trying to sort through the numerous amount of aquatic plants from which to choose. I know it can be overwhelming at times especially when starting your endeavor into nano tanks and adjusting for the size difference.

Nano tanks require a closer look at the microcosm - you basically have to think in miniature. These are just a few of the nano tank plant species that I have had great success without the use of CO2. I perform a ~70% water change twice a week and dose ~3.25ml of Easy Green/Iron/Carbon with each water change. Once they become established and stable, it's really only a matter of constant water changes at least twice a week and spot checking anything that may arise between tank days.

However, please be prepared for a turbulent startup. You will definitely experience at least two algae blooms in the process of setting up your nano tank. Keep persevering and the reward will be tremendous. Feel free to ask any questions.

Stay classy my friends.

EDITED for double spacing.

[Benjix]

I use mine as a quarantine/hospital tank... works very well.

[kaiyas]

I have a 2.5 betta tank and it’s brand new no fish yet. I have a 5.5 betta tank and it has one betta and a snail. I have a 10 gallon betta tank with one betta one snail and a small school of kuhli loaches. I have a 55 gallon tank with an angel fish, a trio of mollies, a school of green neon tetras, a school of cherry barbs, and a school of corydoras. I love my 2.5 and 5.5 gallon tanks best. They’re beautiful, you can put it anywhere you like, it can house my favorite type of fish, and planting it to look nice is much cheaper than planting a 10 gallon.

[rolicaaquatics]

I often tell people - Imagine dropping one drop of food dye into a full bath tab. Then imagine dropping that same drop into a mug! The smaller amount is obviously affected WAY more and that can be a problem with small tanks. When things go wrong, they can go wrong VERY quickly and with big consequences.

[suejudith]

Another great vid! Lots of good info with pros and cons. I keep a few tanks and have 2.5s. It’s planted Diana Walstad style. I also use a small sponge filter. Parameters are always good and the shrimp and fish I have in it are healthy and active. I used to keep some Chili Rasboras and Somphongsi rasboras in it. I now keep Sparkling gourami fry and a lone Rasbora fry in it with Crystal Red shrimp and all are thriving. I use a turkey baster to clean it and do water changes just once a week along with the other heavily planted tanks. The tank doesn’t really require a lot of time from me but when I come home from my 2nd shift it’s therapeutic for me to kind of pick at it 😆

[susannabean]

Another good use that I currently use a 2.5 gallon for would be a brine shrimp hatchery. My 2.5 gallon sits right next to my 20 long guppy/community tank and i use it to hatch brine cysts to feed the guppy fry.

[dimitrinvs]

i kept a single pea puffer in a 2.5 gallon once, was VERY hard. It is however a perfect shrimp or dwarf crayfish tank.

[chefrarestones]

Love your videos!!! They are all so very well thought out and you explain everything so well but leave it for the viewer to see if it will work for them. Thanks for all you do for the hobby!!!

[byz]

Hi Prime Time, @ 2:40, Fish flashing on the right side. Just FYI. Thanks for a cool video!

[willwinn]

I saw my first 5 gallon saltwater fish tank yesterday, it was very well done and had only a few tiny fish .
I couldn't imagine all of the work to keep it so clean and in the right parameters ..
But the whole store was meticulously kept.

[s.d.k]

Thanks for sharing!
But i don't like those size tanks, I prefer 5 gallons and up

[transcyberism]

I use one of these as a hospital/QT tank. Main advantage is it's super easy to do daily water changes if you don't want to maintain an empty cycled QT tank 24/7 or need to dose meds that would mess with a cycle. It is hard to dose meds correctly without a gram scale though! Most med directions assume you're working with 10gal per dose so you'll need to divide everything in quarters.

[Whitewing]

I used a 2.5 for hatching out some rice fish. I'm thinking of setting it or a 5 gallon up in the living room with some plants pulled from a local lake with some snails.

[meggrotte]

Oh wow that's a beautiful guppy tank I think that's going to be my next project a 10 gallon tank filled with guppies of various kinds
I have a 6 gallon tank with a beta who actually likes my guppies and they do very well together

[mbenz]

I do have couple of 2.5 tanks. I’m keeping shrimps and their doing pretty well.

[BradClarke]

I have a 2.5 gallon tank that I've used for a hospital tank for betta, although it has been used to treat a sick zebra danio as well.
My biggest gripe with it is that the glass lid does not leave a gap for a nano heater cord or an air line for a small sponge filter.
May try and cut it down a bit or make one out of acrylic.

[jungleman]

Im planning on using my 2.5 gallon just as a planted tank.