37 Gallon Aquarium Stocking Ideas For Single Species and Community Tanks

37 Gallon Aquarium Stocking Ideas Overview

You would think choosing a 37 gallon tank over a 29 gallon would give you a fair bit more space to have more fish, but the extra 8 gallons is added to the height rather than the length or width, so both tanks have the same footprint.

29 gallon approximate dimensions – 30” x 12” x 18” (L x W x H)

37 gallon approximate dimensions – 30” x 12” x 22” (L x W x H)

Most fish prefer to have horizontal swimming space, rather than vertical so the stocking options are going to be very similar to a 29 gallon tank.

If you haven’t bought a tank yet I’d save some cash and get a 29 gallon, unless you want to keep Angelfish – they’ll appreciate the extra height of the 37 gal tank.

Stocking Aquariums – Things To Consider

Before deciding which fish you are going to put in your aquarium, you need to consider a few things first to ensure your fish will be happy and healthy.

Water pH

Choose fish that are suitable for the natural pH of your water. Use water test strips to find out your pH.

Most fish do well in a pH range of 6.5-8.0, but there are some exceptions to that, South American fish prefer a lower pH (around 6.0), whereas African cichlids and livebearers (mollies, guppies etc.) prefer a higher pH (around 8.0).

If you’ve got your heart set on keeping some South American cichlids and your pH is too high, I’ve gone over some safe and natural ways to lower your pH.

Water dGH

This is your water hardness, the higher the dGH reading the more minerals you have in your water, and this determines whether you have soft or hard water, use the test strips linked above to find out.

Most fish do well in a dGH range of 4-8, however, there are exceptions to this, Discus fish need a low dGH, whereas goldfish, livebearers, and African cichlids need a higher dGH.

Temperature 

Choose fish that thrive in a similar temperature range, putting a betta in with a goldfish isn’t going to work.

Compatibility

If you want a community tank, choose fish that are happy to share the tank with other fish. Avoid overly aggressive fish that will want to pick a fight.

Choose fish that are a similar size, in the fish world, if one fish fits in another fish’s mouth, it will become a tasty meal!

Now we’ve covered the basics, let’s get into why you’re here and go over some awesome stocking options….

37 Gallon Single Species Stocking Ideas

A single species tank is a great option as you don’t have to worry about the different water parameters needed for different types of fish and it can be easier at feeding time.

It’s also a great option if you want to keep more aggressive fish, which would be too feisty in a community tank setup.

You can go with 1 single larger fish or a big group of smaller schooling fish, it’s entirely up to you and what you like the look of.

Choose one of the following options for a single species aquarium.

• 1-2 Fancy goldfish
• 2 Angelfish (1 Male, 1 Female – may breed)
• 8-10 Neolamprologus multifasciatus or similis (shell dwelling cichlids)
• 12 Platies (1 male per 3 females – they breed easily)
• 25 Small rasboras (chili, green kubatai, galaxy etc.)
• 25 Small tetras (neon, green neon, ember etc.)

37 Gallon Community Tank Stocking Ideas

When choosing fish for a community tank, it’s a good idea to pick a mix of centerpiece, community/schooling, bottom dwellers, and algae eaters to create a stunning display that will have fish at every level of the water column and help keep your tank clean.

Centerpiece Fish For 37 Gallon Tank

The show-offs of the aquarium, these fish are beautiful…it’s all eyes on them!

Choose one of the following options

• 1 Angelfish
• 1 Apistogramma
• 1 Betta
• 1 Bolivian ram
• 1 German blue ram
• 1 Honey gourami
• 1 Kribensis

I’ve included betta fish, but this is really dependent on the betta’s personality, some will tolerate tankmates and some won’t, be prepared to house the betta alone if necessary.

Schooling and Community Fish For 37 Gallon Tank

These guys are peaceful and like to be kept in larger groups (minimum of 6) to bring the best out of them.

Choose one or two of the following options.

• 6 Amber tetras
• 6 Black tetras
• 6 Cardinal tetras
• 6 Endlers
• 6 Galaxy rasboras
• 6 Green kubatai rasboras
• 6 Guppies
• 6 Harlequin rasboras
• 6 Marble hatchet fish
• 6 Neon tetras
• 6 Silver hatchet fish
• 6 Rummy nose rasboras
• 6 Rummy nose tetras

Bottom Dwelling and Cleanup Crew Fish For 37 Gallon Aquarium

Some of my favorite fish are bottom dwellers, they are generally very peaceful and you can get some unusual quirky looking fish, like the kuhli loach which has a snake-like appearance.

An added bonus is most of these fish will help to keep algae under control.

Choose only one of the pleco options, and ensure you provide some driftwood for them to feed on and caves to hide in.

Pick one or two of the following options.

• 1 Bristlenose pleco
• 1 Clown pleco
• 5 Julii Corydoras
• 5 Kuhli Loaches
• 5 Otocinclus catfish
• 5 Panda Corydoras

Snails and Shrimps For 37 Gallon Aquarium

These invertebrates are optional but can be a great addition to your aquarium, they help to keep your tank clean and algae under control.

Pick one or two of the following options:

• 6 Amano shrimp
• 10 Cherry shrimp
• 1-2 Mystery snails
• 2-3 Nerite snails

Be aware that some of your larger fish may eat your shrimp, so make sure you provide plenty of hiding places for them, my cherry shrimp love hiding in cholla wood and in and amongst live plants, such as Java moss.

Cherry shrimp come in a huge array of colors and I think they look great in an aquarium, they breed pretty easily and the baby shrimp can be a great free food source for your other fish.

Amano shrimp won’t breed and don’t look as eye-catching, but they are larger than cherry shrimp, so can be a better option if you have larger fish.

Snails require harder water and some calcium to keep their shells strong and healthy, so you may need to supplement if you notice any pitting or cracking.

A lid on your tank is also a must to stop escapees!

Round-up Of Best Stocking Ideas For 37 Gallon Tank

There are so many combinations to choose from, the list is endless! Make sure you do a little research on fish compatibility if you want a community tank setup to check they can live together happily.

I’ve also done some stocking ideas for 3 gallon and 40 gallon tanks if you want some more options.

Check out my best freshwater fish article for more ideas and inspiration, and the aquarium health section for guides and tips to keep your aquarium in tip-top shape.