We have fish tanks and ponds scattered throughout our zone 9b food forest, and they have been a lot of fun.
We usually keep tadpoles, snails, ghost shrimp, minnows and water plants in the tanks. When we come across pests such as aphids or spider mites…into the fish tank they go.
We water plants from the fish tanks and replace it with rain barrel water.
We have come up with some many good uses for fish tanks and ponds in our garden that I consider them to be essential in your garden too!
Read more to learn how we use fish tanks and ponds in our garden!
fish tanks in the garden
Fish tanks are super cheap or free…and we have accumulated a lot of them over the years. We’ve used them to hatch random eggs we find in the yard, they hold critters we catch from the pond. and we turn them into vivariums.
Here are some of my favorite uses for fish tanks in our garden
The basic fish tank setup:
We keep our fish tanks on our screened in back patio, out of the sun.
We get the most use out of our 10-gallon fish tank. We hang a pump filter on the side and use it to house whatever we net in the local ponds and ditches, especially after heavy rains.
We’ve raised and bred snails, ghost shrimp (which you should use a bubbler for not a pump filter), and minnows. From this, my son and I learned that it only takes one snail to have babies, minnows give live birth, and you can see the eggs inside of a pregnant ghost shrimp’s belly.
When we are done studying the critters we catch from the pond, we let them go. Simply rinse the tank out, clean the filter and store the tank for your next project.
fish tank bonus tip
During the spring and summer, we leave our smaller tanks in the yard to fill with rainwater. After it sits awhile, a mosquito or frog will come along and lay eggs in it.
We watch the mosquito eggs hatch into little swimming larvae, then we feed them to our fish.
We do the same for the frog eggs. Then we raise them as tadpoles until we can tell what type of frogs they are.
Cuban tree frogs are fed to our mud turtle, all the other frogs are freed.
Cuban tree frogs get really big and they are eating our native lizard and frog species close to extinction…we do our best to control them on our property and spread the word to others…but unfortunately, they’re here to stay.
Using a trash can as a fish tank. My favorite fish tank setup is with a 50-gallon trash can and goldfish. I hook it up to the overflow of a rain barrel so the water is refreshed every time it rains. This eliminates the need for filters or aerators.
Terrariums and Vivariums
Since the glass holds in humidity, you can use your aquarium to grow all kinds of tropical plants that wouldn’t normally grow in your area…
Fill the with a layer of rocks for drainage (or hydroton), charcoal to prevent smells and rot, dirt, sand (comes in decorative colors too), rocks, and mulch. Then add your plants!
We have a spot in the yard that we dump any rocks, pebbles, aquarium gravel, sand, shells…so whenever we make terrariums, we have a lot of decors to choose from.
What you will need to make a vivarium or terrarium:
Activated charcoal will improve drainage and absorbs any impurities that will cause your setup to mold and smell.
Plants: You can find some awesome plants online or check out the indoor plants at your local hardware store. Make sure to pick something low growing.
eBay such as Carnivorous Plants (seeds or plants) or Calatheas (seeds or plants) which are both great, low-growing plants that will thrive in your high-humidity aquarium.
Amazon: I love Amazon and they also have some good seeds and plants for your vivarium. Air plants, ferns, and live moss are other cool plants to give your aquarium that tropical feel.
A simple spray bottle or fancy plant mister for misting and maintaining humidity. Or you can get an automatic mister that does it for you.
The other day, we found some eggs in the yard. We kept them until they hatched to see what they were. I would have never guessed they were going to hatch into frogs!?! We had fun building them a vivarium which now houses 9 baby greenhouse frogs. This worked out great since the dirt we dug out of the yard had a lot of little bugs and mites in it for the frogs to eat, then I will feed them any aphids and ants I find in our food forest.Use it as a Breeding Tank
One really cool way to use an old fish tank is for breeding minnows, snails or ghost shrimp. We do this so we can feed them to our fish, turtles, and chickens.
Snails are super easy to care for, and they are amazing because they breed and multiply extremely fast! Which brings me to our next cool idea for a fish tank – using it as a breeding tank.
We started our breeding tank when we noticed one of our minnows was pregnant. We moved her into a separate aquarium so the other fish wouldn’t eat her babies.
A day after taking this photo, she had at least 50 baby minnows, and this is how we learned minnows have live birth.
Raising Ghost Shrimp and snails
I’ll never forget the day we caught a ghost shrimp in our pond. I had no clue we had shrimp in there. They are one of my favorite water critters, but they get eaten by anything bigger than them, so we started them their own ghost shrimp tank. They have been bred in some pretty cool colors too.
Freshwater shrimp are easy to maintain and you can house them with snails. If you set it up right, they will breed and multiply really quickly. Below is a picture of one of our pregnant ghost shrimps. Since they are translucent, you can see the eggs inside. Once they hatch, the mom hides her super tiny live shrimps in plants and driftwood so they won’t get eaten.
What you will need to raise freshwater shrimp or snails:
An air bubbler
Snails and ghost shrimp are not very good swimmers, so you will want to use an air bubbler (aka aerator) rather than an aquarium filter so they don’t get sucked up in it.
As long as you don’t overfeed the tank, the snails will do a pretty good job of keeping it clean.
Snails lay their eggs in clear, gooey globs all over the place.
- Raise and study Insect Life Cycles
Raising Insect Eggs and Butterflies
We do a lot of work in the yard and love it when we come across insect eggs, cocoons or caterpillars in the garden. We keep them and raise them up to see what hatches or emerges. It has been an awesome way to learn what types of butterflies all our native caterpillars turn into.
You can start an ant farm in an aquarium too…just make sure you have a really tight lid!
Living in Florida, we have a huge problem with ants. One day, my son accidentally chose to dig into an anthill when putting dirt into a vivarium we were building. Not only did he not get bit, he discovered a really cool way to use a fish tank! Ant Farm!
The ants quickly started tunneling through the small amount of dirt he had already placed in there. We filled it up a little more and carefully dug up some more ants. Not gonna lie, some ants are going to escape, but if you keep them well fed, you won’t lose too many. I just recommend that you leave it outside, ours was on the back patio.
What you will need to raise ants
You can catch your own ants, or purchase them here. (Yup. you can buy ants)
A lid. We poked a bunch of tiny holes into a plastic lid and taped it on top, but they make glass lids such as THESE found on Amazon.
It was cool to watch them tunnel through the aquarium! Due to the hot weather, the lid made it hard to regulate the temperature without cooking them, so we eventually dumped it out, but it was fun while it lasted.
We have always raised mealworms to feed to our chickens, turtles, and fish. They are super easy to care for, they breed quickly, it’s cool to watch their life cycle and the waste they produce is great fertilizer for your garden. Win. Win. Win.
We usually raise them in plastic tubs because they are easier to carry when we have to relocate them depending on the weather, but raising mealworms in an aquarium is nice because it holds in humidity.
One beetle can lay up to 500 eggs…so after a couple of months, you will have quite the collection of mealworms. When done raising them, just put the bugs in a pond or feed them to fish. Don’t let them go in the yard.
What you will need to raise mealworms:
Mealworms – I always order mine from Basset’s on Amazon HERE. Just make sure when you order them you get “LIVE”.
Substrate: a 1″+ layer of cheap oatmeal.
There are other accessories you can get if you want to be serious about it, but as long as you keep them fairly warm and not so humid that the substrate gets moldy, you will be just fine. We made another page that explains in detail how we raise our mealworms. Check it out here.
Raising Frogs from Tadpoles
We keep our extra, unused fish tanks outside by the house and sometimes, they have a few inches of water in them from the rain. Every year, invasive Cuban tree frogs end up laying eggs in our aquariums. It has become something we look forward to every year.
It is usually illegal to mess with tadpoles and frogs, but we have a huge problem with invasive Cuban Tree Frogs here, and it is actually illegal to release them into the wild once you catch them…so we try to do our part to get rid of them.
We will normally feed the tadpoles to our fish, turtles and chickens, but we have raised a few up to frogs and kept them as pets. Cuban tree frogs are cool little pets and would do well in a vivarium. Unfortunately, they are really bad for our ecosystem.
- Use them to get rid of mosquitoes
As mentioned above, we have a lot of fish tanks that we keep in the yard. These tanks accumulate rainwater and eventually end up with tadpoles or mosquito larvae in them. We are always told to get rid of our standing water so we don’t breed mosquitoes, but why would you do that when you can keep your standing water, let the mosquitoes lay eggs in it, then get rid of the mosquito larvae? This prevents thousands of future generations of mosquitoes!
We leave the tanks out, let the mosquitoes breed and lay eggs in the standing water then either put a minnow in it or dump the larvae into our fish tank. I have killed millions of mosquitoes over the years doing this. Genius, right?