Hermit crabs really do need both freshwater and saltwater pools to stay happy and healthy. These little pools aren’t just nice extras, they’re essential. Follow this guide, and you’ll be able to create safe, flowing pools where your crabs can drink, soak, and explore, giving them a little taste of their natural world right at home.
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The Crab Spa: Freshwater Edition
What You Need:
- Water conditioner
- 1-gallon jug
Water conditioner is a product or treatment that dechlorinates tap water, making it safe for hermit crabs (and other aquatic pets). Tap water often contains chlorine or chloramine, which can harm crabs, so using a water primer removes those chemicals and balances the water so it’s safe for drinking, bathing, or mixing saltwater. Seachem Prime Fresh and Saltwater Conditioner is one of my top choices.
Shell-ter by the Sea: Saltwater Edition
What You Need:
- Aquarium salt
- Two 1-gallon jugs
I start by making a batch of freshwater first and letting it sit for a few minutes to ensure it’s ready for the crabs. Once it’s settled, I mix in Instant Ocean Sea Salt to create the perfect saltwater. For my setup, two 2-gallon jugs every couple of weeks is just the right amount to keep everyone happy and hydrated. Instant Ocean Sea Salt is one of my top choices.
The Crab Pools
What You Need:
- 2 Tupperware containers
- Craft Mesh
- Zip ties
- River rocks
Finding the perfect Tupperware for my crab pools took some trial and error, there were a lot of prototypes before I got it just right. Once you’ve got your container, cut the lid so that about a quarter remains on one end to act as a splash guard. Then, use craft mesh to create a little “bridge” over the side of the pool and secure it with zip ties. Finally, toss in some river rocks so your crabs have places to climb and explore safely. Don’t be afraid to experiment and find what works best for you, everyone’s setup and aesthetic choices will be a little different, and that’s part of the fun!
Clean Crab Pools Need an Air Pump
What You Need:
- Air pump: Powers the air stones, ensuring the water stays healthy and oxygen-rich for your crabs.
- Aquarium Tubing: Used to connect air pumps to air stones or create small water features to keep water circulating.
- Air Stones: These keep the water aerated, which is especially important for saltwater pools to maintain proper oxygen levels.
- Y Splitter: Lets you run air from one pump to multiple air stones or tanks, ensuring even oxygenation in all pools.
- Line valve: A small control switch for the air or water flowing through your tubing. In the context of saltwater or freshwater hermit crab pools, it lets you adjust the pressure or flow from your air pump to each pool.
An air pump does double duty for your crab pools: it helps keep the water fresh for longer (around 4–6 days with occasional top-offs) and boosts the humidity in your enclosure, a win-win for happy, healthy crabs.
Here’s how to set it up:
Test the setup, checking the water pressure and placement of the pools and lines, and make adjustments as needed until everything flows smoothly.
Find a good spot to position the pump and route the tubing out of your enclosure.
Connect the tubing to the pump, using a line valve to control pressure, and a splitter to create two separate lines, one for freshwater and one for saltwater.
Cut a small hole in the splash guards and feed the tubing through.
Attach air stones to the ends of each line.
Functional Accessories
Look for every chance to add fun or functional accessories to your crabitat. For example, I added this ladder from HoboHermie on Etsy to make it easier for my crabs to move between the pools, plus, it gives them a little climbing challenge!
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Additional support: Hermit Crab Keepers Checklist