How Many Discus Can I Keep in a 55-Gallon Tank?
Discus fish are one of the most elegant and eye-catching fish that you can have in your aquarium. Though they aren’t the most common of fish (at least not in terms of what you will find in your tank), which is probably due to the fact that they are a little more difficult to care for than other fish.
If you have a 55-gallon tank, the number of Discus that you can have in it is determined by how often you want to clean the tank. If you have 10-15 Discus, you will have to change ¼ of the water, twice a week. If you’d prefer to change it less frequently, you should have no more than 5.
Discuss are capable of getting pretty big too, and a 55-gallon tank will only make them look bigger. Their average size is roughly 5” to 6”, while some are known for growing up to 8” or 9” in length. In fact, a 55-gallon tank is considered to be the smallest tank that you should have if you want Discus.
How Many Discus in a 36-Gallon Tank?
A 36-Gallon tank is really pushing it where owning Discus is concerned. It can be done but you really have to have at least 3. The problem is, that Discus are social fish in terms of being around other Discus.
There are some who would say that you can put a couple of Discus in a 29-gallon tank, however, you’re really getting too small for this breed of fish at this point. A 29-gallon tank and, if we’re being honest, a 36-gallon tank, are just not spacious enough for this beautiful fish to truly stretch out and impress.
A 40-gallon tank is certainly an option, though you don’t want any more than 3, maybe 4 in the tank at any given time. A general rule of thumb is to go with 1 Discus for every 10 gallons of water, however, you can reach a point where the aquarium is simply too small to make for a happy Discus.
The best size tanks that you should have for Discus start at 55-gallons and go up in size from there.
Caring for Discus
Discus are known for being a little more difficult to take care of than your average fish. It’s not that they are incredibly difficult (no one would own them if that was the case) but they require a little more TLC than your typical fish.
If you really want to own Discus, you should consider upgrading your tank size if you have a minimum of 55-gallons. If you’re talking one, maybe two, then it’s not such a big deal. However, from their perspective, rather than yours, more room is a welcome luxury.
You shouldn’t own a shallow tank either, because Discus are nearly as tall as they are long. If you took a frisbee disc and put fins and a fish face on it, you would have a rough idea of how these fish are shaped, along with their size.
When you are as tall as you are wide, your up and down matter as much as your left and right.
Water Temperature and pH
Discus are a warmer breed of fish. Their preference for warmer temperature water means that you may have to rethink the diversity of your tank, considering only fish that share the Discus’ affinity for warmer temperatures.
Discus prefers their water temperature to be around 85°F, plus or minus a few degrees in either direction. Young Discus prefer it hotter than that, so you can err on the side of caution with them and keep the tank a little warmer.
Of course, this also means making adjustments in how you aerate the water and how often you refresh the water in the tank. Hotter water temperatures minimize the oxygen levels, so it has to have a higher level of aeration.
This also means changing the plants that you keep in the tank as well. Most aquatic plants that we choose for our aquariums don’t prefer the hotter water temperatures either so you will want to focus only on the plants that do.
Discus are used the waters that are native to the Amazon, hence the preference for warmer water temperature. That also means higher acidity and soft water, with a pH that is below 7 and a gH of 2.
You can go up or down in small increments, especially to accommodate other fish, as Discus fish are very hardy and they are capable of adapting to water conditions that are a little outside of their norm.
One of the best filtration systems that you can use in your tank is the right choice of plants. Plants help to filter the water all on their own. The ammonia build-up that takes place over time, mostly as a result of the existence of fish in the water, is sucked up by the plants, along with a healthy dose of nitrates.
The plants will effectively remove the harmful nitrates and ammonia while dispersing their own oxygen into the water. It’s a great way to reduce your own maintenance on the tank, as the plants do a lot of the hard work for you.
Of course, if you have a much larger tank than the above-mentioned, 55-gallon variety, you will need more plants to handle the larger ecosystem. Purchasing a substrate such as UNS, helps your plants blossom to their full potential, while also stabilizing the water.
The smaller the tank, the more often you will have to change ¼ of the water, however, having several plants in the tank helps to alleviate this chore somewhat, so you can effectively cut down on the number of times that you have to do it when you are dealing with a smaller tank.
All Things Considered
Although you can have up to 15 Discus in a 55-gallon tank, you should really limit the number to 1 Discus for every 10 gallons of water. That way, you won’t have to deal with an insane amount of maintenance on the tank each week. Also, keep in mind that plants are an excellent filtration system on their own, so the more the merrier.