It’s commendable that you’re seeking the perfect tank size. I have various tank sizes suitable for different purposes and types of fish.

Since you’re a beginner, I assume you’re pursuing this as a hobby, aiming for the well-being of your fish without encountering too many challenges. Even if you’re considering a breeding tank, I have recommendations for that scenario as well.

Are larger tanks preferable?

In a word, yes. You probably want to avoid frequent water changes, fish diseases, cleaning hassles, and, most importantly, stress. These are just a few issues associated with smaller tanks, but there are many more. However, it’s essential to note that you should opt for a tank that is wider rather than deeper because a larger water surface area is better for your fish.

Nevertheless, a larger tank offers:

1. Great flexibility for adding new fish
2. Ease of cleaning
3. Ample space for aquascaping, planting, hiding spots, and more

Despite understanding the problems related to smaller tanks and the benefits of larger ones, keep in mind that these are guidelines for the betterment of your fish. You can still choose a variety of fish according to your preferences.

Common Myths about Tank Sizes

We’ve all heard various rules such as fish capacity rules, which suggest something like one inch of fish per gallon or a specific ratio of water surface area to the fish’s body length. These rules are flawed as they don’t account for filtration. Therefore, don’t take these rules as gospel; they’re merely rough estimates.

It’s kinda scary as a beginner and feels like there are so few fish in the tank, but no worries. I follow 1 fish per 2 liters, and understand the fish, whether they have any territorial behavior or aggression. Look, you need to care about your water parameters and filtration. As long as they are fine, your fish are going to be fine. Finally, you need to know that more fish means more maintenance.

It’s worth mentioning that you shouldn’t go for a tank smaller than 5 gallons, as this could potentially dampen your interest in this hobby due to the numerous challenges it presents.

Variety of Tank Sizes

5 Gallons

These are beginner-friendly, and you can keep one betta or rasbora inside a 5-gallon tank, as they are hardy and can withstand varying weather and environmental conditions. Small tetras can be also kept here. This is the minimum size you should consider unless you have no other options; in that case, I recommend opting for a larger tank.

Size: 16×8×10 inches

10 Gallons (Ideal for Beginners)

This would be a good choice for any beginner, except if you’re specifically looking for a breeding tank. In a 10-gallon tank, you can easily accommodate different species of fish, such as small schooling fish, and small tetras like ember. Remember, the larger the tank, the more flexibility you have in terms of design; you can incorporate various decorations, plants, and filters, and you can introduce new fish mates as well.

Size: 20×10×12 inches

20 Gallons

These sized tanks offer ample space for several schooling fish, and different species of barbs and most common for this size is three spot gouramis and this tank can be used for breeding purposes. If you have the budget and intend to stick with this hobby, I recommend investing in a 20-gallon tank; otherwise, a 10-gallon tank will suffice.

Size: 30×12×12 inches

29 Gallons

This size is quite substantial. This can be a great option for freshwater aquarist. This tank offers stable water parameters without too many cons except it’ll require a stand to hold. Here, you can incorporate filtration systems, LED lights, and other accessories, making maintenance easier without consuming too much time. You can house tetras, neons, cory catfish, and other large schooling fish in a 29-gallon tank. I have pet angelfish and some bottom dwellers also and they perform well in this tank. It can be a breeding tank also.

Size: 30×12×18 inches

40 Gallons

This is a type of tank that I recently loved and my beautiful flower horns you can see from the picture below are happy. You can easily accommodate 3 or more fancy goldfish and white cloud minnows. For breeding, it is also sufficient.

Size: 36×16×18 inches

55 Gallons and above

While tanks of this size are available, I wouldn’t recommend them for beginners. They require higher maintenance costs compared to the previously mentioned sizes. However, if you’re interested, you can certainly explore this option. However, if you’re interested, you can explore this size further. Although it is a nice choice for oscars, redtail sharks, and some larger cichlids.