Looking for something colorful to liven up your tank? Perhaps something that works well in a group and shoals for some entertaining observations in the tank setup?
As the name suggests, something with the word rainbow in the title should indicate that this is a colorful species with a lot to offer the hobbyist. And yet those in the know appreciate this isn’t always the case — we’re looking at your Rainbow Shark!
Joking aside, the Boesemani Rainbowfish (Melanotaenia boesemani) is a gem of a tropical freshwater fish that is native to Indonesia. Found only in a few shallow areas of a handful of lakes known as the Ayamaru Lakes, any of the Boesemani Rainbowfish you will find on the market will be bred in captivity. They should not be sourced as wild-caught fish as they are on the endangered list.
These fish are easy to care for, generally peaceful, and can survive quite a long time, making them ideal for starters in the hobby who are looking for some vibrant zing in the tank.
With their simple yet elegant color pattern, moderate size, and good nature, you’ll be on the lookout for a Rainbowfish in no time.
Let’s take a look at what’s at the end of the rainbow to discover more about this fascinating fish and why it’s so popular with enthusiasts.
Boesemani Rainbowfish Behavior
With a shoaling fish, you know you’re going to require a group to show them off to their full potential, not to mention be considerate of their psychological needs.
They are highly social and love to be amongst their own kind, which makes them ideal for community aquariums. You will often see them actively swimming and zipping about the tank showing off their personalities to their fullest. Good to note here that this can stress out more timid fish species, so they are best matched up alongside other active and busy fish who won’t be intimidated by the hive of activity!
They will usually occupy the middle levels of your tank and will mix well with suitable tank mates without too much fuss.
Boesemani Rainbowfish will also exhibit variations in their color that will help you identify if they are healthy and happy. While this will be more noticeable in the more vibrant males, it’s a good indicator of how your shoal is feeling about their habitat.
They may intensify their color when feeding time arrives, too, as they tend to get rather excited about food and can be greedy when it comes to eating.
Another point to note about these fish is that they are quite reactive to distractions and noise outside of the tank and can be described as skittish as a result despite their active swimming tendencies. Better to keep these fish in tanks with low-traffic areas that are not close to entertainment systems and multimedia sources.
They are often calmer when they have a gang to hang out with. Schools of six or more are ideal; anything less than six may make them feel vulnerable. You’ll also want a higher ratio of females to males to avoid harassment when breeding times are on the cards.
Watching them shoal is a rewarding part of having this species as they will show off their dual coloring (at least the males will), but even the silvery females will look sharp against their ideal habitat with lots of vegetation.
Boesemani Rainbowfish Lifespan
If you cater to the needs of your Boesemani Rainbowfish, you could expect them to live for on average around 5 – 8 years. They can live longer though, 12 years is not unheard of if you have lavished them with the attention and care they need.
We will discuss more on tank requirements a little later in this article.
Boesemani Rainbowfish Appearance
These fish exhibit sexual dimorphism, which is to say that the males are visibly and obviously different looking from the females of this species as adults.
The males tend to be the prized gender because they are a tale of two halves.
In males, the posterior half of this fish is usually yellowy-orange, while the anterior half of the fish is bluish-purple. They are practically split right down the middle on a side view. Males can grow up to 4.5 inches in length.
Females, on the other hand, are less vibrant and have a brownish-green dorsal zone that fades to silvery-white on their bellies. They usually reach about 3.0 – 3.5 inches in length.
In both cases, they are like a gently flattened oval in body shape with quite small fins. The dorsal and anal fin are super short and compact, not reaching far off the body and start near the midsection and run to the caudal. The caudal fin itself is quite small in stature, and they have small, almost translucent pectoral fins.
As juveniles, they will look similar before the males’ color intensity increases, so it can be tricky to know just how many of each you’re getting!
As they mature, the beauty of these fish is undeniable, with their complimentary coloring beautifully capturing the magic that is blue and orange tones.
Boesemani Rainbowfish Habitat And Tank Requirements
As always, we want to achieve optimum health for fish we keep in captivity by closely mimicking their natural habitat. Their wild origins are the shallows of only three freshwater lakes in Indonesia, with a lot of natural vegetation available to them.
Let’s look at some specifics that are needed to provide these fun-loving fish with a great quality of life that best suits them for optimum health.
Tank Conditions
Moderate water flow is good for these fish who like their active swimming space. A hang-on back filter will usually do the trick nicely for these fish.
A fitted lid will help avoid any accidental excursions from the tank, as these guys are known to jump too.
Dense vegetation helps these fish feel secure and allows them to hide when they feel skittish or just need a break from the shoal.
Good plants to incorporate into your setup would include things like Java Fern, Rotala Macrandra, Red Tiger Lotus, and Ludwig Ovales. You’ll want to keep things from being too tall unless they are at the rear of the tank as a backdrop. This is to enable them to utilize the middle section of your tank for open swimming.
Rocks and driftwood additions are nice to include too, just ensure your driftwood is thoroughly rinsed to avoid any acidity in the tank.
These fish like alkaline, hard water that is suitable warm. A heater must be incorporated if you don’t live somewhere tropical yourself to provide consistency.
Consider a darker substrate in your setup, too, as it will help provide contrast to really show off their coloring. You can use coarse sand or rounded gravel for these fish as they have plenty of scales and aren’t going to be hanging around on the bottom layer.
Water changes will need to be weekly and at least 25% changed over.
Water conditions should be noted and maintained as follows:
- pH of 7.0 – 8.0
- Water hardness between 9 – 19 dKH
- Temperature between 80 – 86ºF (26 – 30ºC)
- Lighting on moderate to low levels will make their coloring stand out
Tank Size
The minimum tank size for a group of six is about 30 gallons, and if you add more, then add another 5 gallons for each individual.
However, this is the minimum, so getting something larger is even better to keep them active, curious, and healthier.
In terms of shape, you’ll want something long and rectangular that will allow them plenty of active swimming areas and lengthy bursts of activity. Avoid anything rounded that will impede their schooling nature.
Choosing Tank Mates For Boesemani Rainbowfish
When it comes to finding friendly species for your peaceful Boesemani Rainbowfish, you have plenty of options.
Keeping things like other active fish in the mix who won’t be stressed by their active swimming moves is ideal.
As usual, we want to keep sizes of tank mates relative, nothing too small your Rainbowfish might try to consume, and nothing too large that may want to consume them!
Some excellent tank mate pairings that really would work well include:
- Dwarf Rainbowfish
- Turquoise Rainbowfish
- Zebra Danios
- Loaches
- Corydoras Catfish
- Otocinclus
- Congo Tetras
- Celestial Pearl Danios
- Blue Acara Cichlids
- Rainbow Cichlids
- Guppies
- Barbs
- Rasboras
Feel free to add in invertebrates like Ghost Shrimp for tank cleaners, and things like Assassin Snails are a good match too.
Notes On Feeding Boesemani Rainbowfish
As we mentioned earlier, these fish are prone to getting greedy when it comes to feeding time and are not picky eaters. They are omnivores by nature and enjoy plant matter as well as small proteins like larvae and worms.
Boesemani Rainbowfish will indicate their health status by their coloring. If they are getting the right amount of nutrients that are diverse in their sourcing, they will be vibrant and stand out.
If you only provide poor-quality flake and pellet foods with no supplementation with live and frozen foods, you can expect them to look pale and dull in comparison. Bloodworms, Daphnia, and Brine Shrimp, are all easily accessible food sources in the hobby and will help you develop those brilliant colors.
Always try to have the best quality flake or pellet foods and include frozen and live meals regularly.
Blanched veggies like zucchini, spinach, or cucumber can and should also be included in their meal plan, but be sure to remove any untouched food to avoid water fouling.
You’ll want to feed these guys a minimum of twice a day and allow them to consume what they can in no more than a few minutes to prevent overfeeding.
Boesemani Rainbowfish Common Health Issues
Most freshwater fish are susceptible to Ich (White Spot Disease), which, as the name implies, is easily distinguished by white spots on the body due to a parasitic infection.
Ich is treatable when caught early and suitably medicated. If left untreated, Ich is usually fatal. Raising the tank temperature for two weeks will usually get rid of this parasite and eradicate the issues.
Fin Rot can also occur with these fish but can be harder to spot since their fins are so short!
Normally these issues happen because the water parameters and quality have dropped. This means upping your game and schedule without fail to restore the tank to its best.
They can be minimized with a strict water cleaning and change schedule along with regular checking of your water parameters.
How To Breed Boesemani Rainbowfish
If you wish to explore a breeding project, then Boesemani Rainbowfish is a great way to get yourself started!
Their sexual dimorphism makes it easily apparent who your mature males are from your females.
Slightly increasing the tank temperature can help things along if you want to encourage spawning. Males will usually turn more vibrant when spawning is apparent. A breeding tank is useful if you have identified a pair.
These species are egg scatterers, and they usually like flat vegetation to do so. Males will perform a display to encourage the females to spawn then fertilize the eggs wherever she lays them. Spawning will occur on and off for several days, so don’t remove the pair from the breeding tank too early!
Adult Boesemani Rainbowfish are not known to be prolific consumers of their own eggs like so many other species are. They will ignore the fertilized eggs so they can be removed from the tank for an easy life once spawning has finished. Fry usually hatch after 7 – 12 days or so and like to hang out near the water surface or hiding in the vegetation.
Tiny food sources are what is required to keep your baby Rainbows growing, so microforms are good until they can eat baby brine shrimp and other types of fry foods like infusoria.
Are Boesemani Rainbowfish The Right Choice For Your Aquarium?
Overall, these fish are an enticing proposition as a starter fish for the starter hobbyist. They are equally admired by experienced aquarists because they are so easy to get along with yet retain that flashy color so beloved by those in the hobby.
Often many of the flashier fish can be quite aggressive, which makes composing a community trickier, but not with the Boesemani Rainbows.
As long as you choose wisely to accommodate similar water conditions, these fish will be delightful and rewarding to raise with eye-catching displays and bags of personality on offer.
Get yourself in on the action with the fish; you won’t be disappointed!
