that’s awesome!!

i mean, it all really depends on your goals. costs for both hardware and fish can be really affordable depending on what you set out to do. each species has different requirements and while some can be kept together, for the intention of breeding, it’s usually best to keep them as a single species tank.

i assume your knowledge surrounding the hobby is limited, so knowing your own goals might not be feasible right now. usually, people start out by getting a single fish at the pet store, learning more about it, about other fish, and eventually finding their passion.

if you just want to keep an affordable fish to ‘try’ the hobby. your absolute, without a doubt, best option, is a betta. they’re the most popular species because they hit so many marks on what first-time keepers are looking for. brilliant colors. affordable. variable personalities. and incredibly low maintenance (this could also be a bad thing, since they’ll survive just about anything in terms of what fish can handle).

before i go into details, i’m just going to point out that there are certain expected standards, i don’t want to explain why things are a certain way at every point as i’d run out of words in this post. if you have questions though, feel free to ask :)

so to get to it, betta splendens costs.

• you’ll want a 12 gallon tank to start. bettas theoretically don’t need 12 gallons, but it’s usually standard minimum aquarium size by law in some countries. these usually come very cheap on second hand markets (i’ve bought many in the range of $10-$30). if buying second hand, make sure it comes with a light panel, and to ask when last the aquarium was active, if it’s been over a year since last, the silicone might have a leak and will need to be patched (aquarium silicone is about $10). if it has a light panel, but no light, a new light is usually another $10.
• you will not need an aerator or pump. unlike most fish, bettas have a lung-like organ and will breath air from the surface. bettas also pollute very little compared to most fish species. for your own convenience though, getting a hang on filter will reduce water change requirement and disturb the surface so it doesn’t get clogged with algae. a hang on filter cost around $8.
• water heater. bettas are tropical and unless your room temperature is at a stable ~75F, you will need a water heater. if water temperatures go below ~60F, your betta is at risk of entering a comatose state and drown. yes. drown. bettas are happiest in 72F to 86F. if you need a water heater, it will cost you around $6.
• plants! you’ll want some big leafed plants in your aquarium, or rather, your betta will want some plants to sit on. they’re mostly sedentary fish, conserving energy since they don’t normally breathe with their gills. not all bettas are lazy though (in my experience, 1 in 10 seek adventure), but seeing as this is your first time taking home a fish, there’s no way to tell what kind of personality your betta has. anubias is a great starter plant, they have very low nutrition and light requirements (just like the betta), grow very slow so need very little maintenance. anubias usually sells for around $20, but you can probably find a small second hand $1 to $2. as for general decoration of plants, java ferns is another of my personal favorites, very low requirements like anubias, but grow fast and looks pretty, usually sells for $3 at the stores. ambulia is another decorative and super easy cheap plant that grow like a weed and might actually need a lot of trimming to deal with.
• gravel balance the bacteria flora of the tank. now, bettas don’t technically need gravel, or plants, or bacteria, or anything. it’s a fish with very low requirements that essentially live in oxygen starved ditches in the wild. but it does help with maintenance to have both gravel and plants, as they keep chemical levels in check and reduce water change needs. a pack of gravel for a 12 gallon tank can cost as low as $5 as bettas don’t utilize the gravel for anything so anything will do.
• feed. bettas will eat pretty much anything, but to avoid the fish from getting bloated or sick, high grade standard feed like dr bessleer is recommended. 100g of dr bessleer should last months for a single betta and cost around 10$. occasionally mixing it with some frozen bloodworms or cyclops for extra nutrition will cost around $5 every ~3 months or so. personally, since i have a lot of fish to deal with, i farm my own daphnia, blackwroms and artemia, which costs me around $15 per year in maintenance; but i consider it next level since it’s extra work and a single betta don’t consume nearly enough food for it to be worthwhile.
• water quality. bettas live in ditches that can have near toxic conditions. of course, we want the fish to be happy. but due to their hardiness (or complete disregard for what a normal fish would think), they will be happy in pH ranges from 5 and up to 8. with hardness from as low as 18 and up to 268 ppm. so you probably don’t need any chemicals to deal with the quality. depending on what kind of water access you have, of course. chemicals that might be needed can range from $3 to $8 per jar/bottle. almond leafs are good additive for chemicals to keep bettas healthy though, add $2.
• cycling. now, bettas don’t technically need cycling, again because of their hardiness. it is always good (for your own maintenance requirements - cycled water = less water changes) to cycle an aquarium before getting your fish. since it’s a betta though, you could probably get bacterial liquids ($4) and just put the betta in right away. keep checking the water quality and see if the levels spike too hard and need a water change. personally, when i started breeding them, i setup a water change system for changing 100% of the water every 3 days - but i have my own tap water supply, so don’t need to dechlorinate or such.
• cleaning tools. you’ll want a water changing pipe to suck and filter detritus and water while changing, costs around $3. you probably already have a bucket, but otherwise that’s another 3$. and you could get an algae scrubber but i just use one of those fresh dish scrubbers for 2-3 cent at nearest supermarket. you will also want a cheap water test kit to periodically test your water, that’s around $3 (how often you use them varies a lot on conditions, a single tube can last a whole year).
• electricity, i don’t know your rates. you need to check the lamp and the hang on filter.
• finally, the betta. now bettas are among the “pricier” fish in the trade, mainly because they’re near exclusively imported from specialist breeders in south east asia. so on average, betta will cost you $15. bettas are generally very healthy fish species that don’t need medication. most common condition is fin rot, which mainly just needs water changes and reduced stress. you can read more about that online.

overall maintenance for the aquarium varies. your main efforts will be feeding the fish once or twice a day. bettas don’t eat a lot despite their size, but you’ll have to figure out just how much volume to feed your fish since any feed that isn’t consumed will spoil and deteriorate the water quality. water changes take 5-10 minutes and the bigger the aquarium, the less often they need to be done. in a 12 gallon tank, you’d probably want to do 20-50% every ~3 weeks before you hit that sweetspot balance (i change water about every 3 months).

total cost for starting this trial experiment: $80-$110. and then around $10-$30 a year for consumables, depending on your budget and how you want to do things.

now, breeding bettas is an entirely different beast. this is where the actual costs and work come in, because bettas, unlike most other aquarium fish, cannot be kept together in the same tank. which requires your interference to make it happen, and space… a lot of space… too much space… ugh. there are cheap-ish ways to do it, but space is always the issue, and if your goal is breeding. there are easier options. if you want to know about betta breeding, i can explain it in another post though.

ANYWAY, so that’s for the bettas. They’re the most forgiving fish to deal with, if you just want to try keep a fish and see how it goes, which is why i detailed it for you. the next introduction level, specifically for breeding, is the guppy. and for the same reason, guppy is the second most popular fish in the hobby. but to start out breeding in a semi-serious manner, you will need 3x 15 gallon aquariums. for developing entirely new strains and explore genetics, you’ll need a minimum of 8x 15 gallon tanks. guppies are dirtier and hungrier fish and need pumps, aerators and, a lot more feed. which adds to cost and more water changes. i can go into detail if you’re interested.

if you have limited space, but want to try something super easy, you could just specialize on shrimps. neocardina shrimps (aka cherry shrimps) will breed without interference, have minimal space requirements (nano tanks at 6 gallon is enough) and like the guppy and betta, come in a myriad of selectively bred colors.

and there is another interesting ‘take’ on the fish hobby, known as “summer tubbing”, the practice of keeping a small pond on the balcony (in the form of a large flower pot, or tub - no electronics necessary), and there are two particular species of fish perfect for this practice that will breed actively without interference. the most popular being white cloud mountain minnows and the new-to-the-west, medaka. this is my current main niche.

if your goal is conservation breeding, goodeid is another easy start.

for hardcore advanced level fish keeping, which i would not recommend to start, saltwater, predators, and large ponds is the main. pond keeping is a different beast altogether. koi/goldfish is ‘easy’ as in, hardy, but it requires a lot of money, work and space.