Congratulations! Your clownfish are laying eggs and you’re thinking to yourself, “Hmmm, wonder if I can raise some baby clownfish?”
Why, yes… yes you can.
However, there is a lot of work that needs to be done before successfully hatching clownfish eggs. There is even more work for raising the fry! But don’t worry, this guide will walk you through everything you need to know. I’ve raised thousands of baby clownfish following these methods and although it’s a lot of work, clownfish are one of the easier marine fish to raise from eggs.
How Many Days Before Clownfish Eggs Hatch?
Once clownfish begin laying eggs they’ll typically stick to a schedule. After the eggs are laid, they will be ready to hatch in about 6 to 8 days. The time it takes to hatch depends on several factors, including temperature of the water and species of clownfish.
The best way to know when they will hatch is to keep track with a calendar. As long as the environment stays stable, the eggs will always hatch on the same day. When you know that your clownfish have just laid a clutch of eggs, start keeping track on the calendar. Mark the day they are laid as day 0. If you find that they hatch on day 7 after being laid, then you can be sure that the eggs will always hatch on day 7. This assumes that everything else remains stable (temperature, parameters, etc.) and that you started counting as soon as they were laid.
If you aren’t sure exactly when the nest was laid it can be more difficult to determine when the eggs will hatch. However, on hatch day, the eggs will look very silver. This is because the egg itself becomes almost completely translucent and you can see the clownfish larvae clearly inside. If most of the eggs are silver and you can see their eyes inside the eggs, then they will likely hatch that evening.
What Time Will Clownfish Eggs Hatch?
Clownfish eggs always hatch at night when it’s dark. When you’re hatching eggs at home, the best bet is to have a separate hatching tank ready for them on hatch night. This should be in a place where you can have complete darkness – so not a busy room where people will be popping in and flipping on the light.
On hatch night, the tiny fry will begin to emerge from the eggs within a couple of hours after the lights go out. They will usually all hatch within a few hours once they start. If they don’t all hatch on the same night it is possible to leave them in the hatch tank for one more day to see if more will hatch (just follow the rest of the steps below but keep the eggs in the hatch tank for one extra day).
After hatch night (or after the second night at the latest) you should remove the tile or pot and clean it so it’s ready to swap back into your breeding tank.
Options for Collecting Clownfish Eggs
As mentioned in our How to Breed Clownfish Guide, you have two main choices when it comes to spawning environments: letting your bonded pair lay eggs directly in a display tank, or setting up a dedicated breeding system.
If you are running a separate breeding system, your best route is Option 1: moving the eggs safely into a nursery tank before they hatch. However, if your fish are already spawning in a community display tank, Option 2 will walk you through exactly how to collect the delicate larvae on hatch night.
Here is how both methods break down:
Option 1: Removing the Eggs Before Hatch Night (The Easiest Route)
If you catch your clownfish preparing a nesting site, your goal is to get them to lay their clutch on an easily removable surface.
- The Lucky Scenario: Sometimes a pair will choose a small rock or decorative element that you can simply lift out of the tank a few hours before they are scheduled to hatch.
- The Pro-Breeder Trick: If they are currently laying on your permanent reef rockwork, wait until they finish their current cycle. Then, place a small 4×4 or 6×6 inch unglazed ceramic tile or a 4-inch terracotta clay pot directly over their favorite spot. Clownfish are aggressive creatures of habit; next time around, they will usually clean and accept the new tile or pot as their permanent home.
Option 2: Collecting Larvae After They Hatch (The Display Tank Method)
Letting the eggs hatch directly inside a populated display tank is a viable option, but it comes with a major hurdle: catching microscopic, fragile larvae in a large tank in the middle of the night is incredibly difficult.
To pull this off successfully, timing is everything. Clownfish eggs almost always hatch within a few hours after the tank lights go out. The moment the lights turn off, you must shut down all powerheads, return pumps, and filtration. Leaving them on means your newborn fry will immediately be lost to the filtration system or killed by pump impellers. Note: Monitor your time closely, as leaving your main system turned off for too long can deplete oxygen levels and damage your display tank.
Once the pumps are off, you can choose between two collection methods:
- The Flashlight & Bowl Technique: Newborn clownfish larvae are naturally drawn to light. Hold a small flashlight flush against the glass right at the water’s surface to create a localized beam. Once the fry gather in the glow, gently scoop them out using a small plastic bowl or specimen container. Never use a fish net, as the mesh will fatally damage their fragile bodies. Move them immediately into your pre-prepared grow-out nursery tank.
- The Vossen Larval Trap: If you don’t want to spend your midnight hours hovering over the tank with a flashlight, you can deploy a specialized tool like the Vossen Larval Trap. This ingenious, passive device sits inside your tank on hatch night, using a low-intensity light source to safely lure and capture the swimming larvae so you can easily transfer them to a rearing tank the next morning.
You can watch exactly how the larval trap operates in the real-world setup below:
What to Prepare Before Raising Clownfish
Prior to even thinking of raising clownfish from eggs, it’s vital that you have live food for the larvae. In the wild, clownfish larvae eat plankton – tiny, microscopic plants and animals. In captivity, the most readily available food for clownfish larvae are rotifers. They will not eat dry food for at least the first few days of their lives and will not survive without rotifers.
Reed Mariculture has a good article on culturing rotifers. If you can’t culture and maintain the rotifers then your efforts at raising baby clownfish are doomed.
Hobbyists often ask if clownfish larvae can eat newly hatched brine shrimp (nauplii) or copepods. Unfortunately, the larvae are simply too small when first hatched to eat baby brine shrimp or copepods and rotifers are really the best available option. The bottom line is if you can’t raise rotifers then you are going to have a very tough time raising clownfish fry.
Clownfish Hatch Tank and Rearing Tank Setup
Hatching out clownfish and seeing them through metamorphosis is by far the most difficult part of raising clownfish. Proper tank setup is a crucial step here. There are a couple of different ways that people have had success with this, but I’ll explain what has worked best for me.
Have a 10-gallon fish tank ready and cleaned out very well. You should use a bit of bleach to clean the tank then rinse it very well with a bit of vinegar, then with clean water. If it is not cleaned and rinsed well it will kill the fry. You can skip the bleach if you prefer – just make sure to use very hot water and clean the tank thoroughly. Do the same with everything that goes into the tank.
You’ll need a heater (100 watts works well for a 10-gallon hatch tank), a thermometer, an air stone and a sponge filter to go into the tank. The sponge filter should be seeded for at least a week in the breeding tank, so it collects some of the beneficial bacteria. Do this by simply placing the filter sponge in the breeding tank, which allows it to collect the beneficial bacteria essential for breaking down toxic ammonia and nitrites. Larval tanks accumulate waste quickly from heavy feeding, and moving a pre-seeded sponge is the only way to prevent a fatal ammonia spike on day two. This does not need to be cleaned when moving it from the breeding tank to the hatch tank. Have a few filters, so that you can clean between hatches and always have one seeded for the next hatch.
You want to adjust the heater to the same temperature as the breeding tank and make sure that it can hold the temperature stable. Use black electrical tape to black out the small light that turns on when the heater is on. If you don’t do this, the fry will be attracted to the light and can die from the heat.
The 10-gallon tank should be blacked out on all sides. This can be done by painting three sides (leave one unpainted), with construction paper or cardboard, or as I used, insulated wrap like this. You don’t have to use insulation; I just did because I thought it would help keep the temperature more stable. Place something temporary on the fourth side (the front) of the tank, which can be removed later, such as cardboard or construction paper.
You’ll also need a light source. I used inexpensive LED hoods from WalMart (like these). To adjust the amount of light I simply covered the top of the tank with a piece of reflective wrap or cardboard and pulled it out until it allowed the correct amount of light into the tank. You can use anything, just make sure that you can adjust the amount of light. When the fry first hatch you want the tank to be very dim. Too much light can actually cause the fry to die.
To fill the tank, I put three gallons of freshly made water into the 10-gallon tank, making sure the specific gravity was the same as the water in the breeder tank. Then, take two gallons of water from the breeder system and put that in the tank so that there are five gallons of water in a 10-gallon tank. I do this all on hatch day, giving the water temperature enough time to stabilize before the lights went out.
What to do on Hatch Day
On the day that your eggs are scheduled to hatch, have everything ready well before the lights normally go out. Don’t suddenly change the lighting schedule – ensure you’re ready before the lights are normally scheduled to go out. Have the water in the hatch tank as outlined previously, with the temperature stable and the air bubbler running (the sponge comes later).
About an hour before lights out, move the eggs from the breeding tank to the hatch tank. Don’t over think this. Just reach in, grab the pot or tile, and quickly move it from one tank to the other, replacing the pot or tile in the breeder system with a clean one.
Once you have the eggs in the hatch tank you need to set up the air bubbler to run over the eggs. If you’re using pots, I found the easiest way was to lay the pot with the eggs at the top. Put the bubble stone at the bottom of the pot and as far back into the pot as I could. That way the air would hit the top of the pot and run out, directly over the eggs. Sometimes the bubbles hit the eggs directly too and I didn’t have a problem when that happened. You just want to make sure as many of the eggs as possible are moving. If you have eggs that aren’t moving, you should try to adjust it as much as possible to cover as much of the nest as you can.
Finally, ensure that your rotifer culture is ready. They should be well-fed on high-quality green algae, and you need to have your rotifer sieve ready to go for feeding after the hatch is done.
Waiting for Your Clownfish to Hatch
Once everything is set in the tank – the air bubbler is running over the eggs, the lights are on, and you are otherwise ready – wait for the time when the lights go off in your breeder tank. At that time, turn off the lights on your hatch tank. Ensure that there is no light getting into the tank, turn off the lights in the room if you can and leave the room so you don’t disturb anything.
There are two options at this point:
- Check the tank after at least two hours.
- Wait until morning to check the tank.
I find that I have better survival rates when I check after two hours and prepare the tank as outlined below. However, if you check and see that a lot of eggs didn’t hatch then it would be best to wait until morning. Healthy larvae should be able to survive until morning with the egg sacks.
You don’t want to bust into the room and turn all the lights on. You can literally scare the larvae to death doing so. It’s best to check with either a very dim flashlight, or if possible, a red light or a flashlight covered with red film. When you check, you should see hundreds of tiny larvae swimming freely in the tank!
Whether you check on hatch night or wait until morning, once the eggs are done hatching you are ready for the next step.
How to Feed Rotifers to Newly Hatched Clownfish Larvae
You can now remove the pot with the hatched eggs. There may be a few that didn’t hatch either because they died or weren’t strong enough. As long as it’s not a significant portion of the eggs there is no need for concern. Most of the time you should get nearly all the eggs to hatch. The pot can be cleaned for the next clutch now.
Next you need to tint the water and add rotifers to the growout tank. To tint the water, just take some of the liquid algae that you feed your rotifers (such as Reed Mariculture’s) and put it in the growout tank. I found it best to take a bit of the tank water (be sure not to have any babies in the water) in a separate container, mix a heavy amount of the algae really well in there, then distribute that into the growout tank and mix it gently so it doesn’t just settle to the bottom of the tank.
The final color should be quite dark green. You want it thick enough so that you can’t see the back of the tank when looking through the front, but you should be able to see several inches into the tank when looking at it.
Once the tank is tinted, add your rotifers. Use a rotifer sieve by pouring some of your rotifers over the filter into a bucket or sink. Don’t pour rotifer water directly into the growout tank!
Now you can turn on the light source. It may take a bit of experimentation to get the lighting just right. To begin, it’s best to have the light at one end of the tank, while the other end is quite dark. This way if the larvae are getting too much light they can move to where they are more comfortable. Having the tank properly tinted with algae will also help, since less light will spread around the entire tank. Even the lit end should not be extremely bright, however.
One sign that there is too much light would be if you see the larvae swimming away from the light and gathering either in corners or edges of the tank. They should swim freely in the water so they can hunt rotifers. If they are avoiding the light, then they aren’t eating and will soon die.
Transitioning Clownfish from Rotifers to Prepared Foods
The larvae will need to have a constant supply of rotifers for about the first 10 days of their lives. On about day five you can begin feeding newly hatched brine shrimp if you desire. However, it isn’t necessary and it’s easier to just go from rotifers to dry food.
The first dry food offered should be TDO – A, which is top-dressed Otohime. This is simply a high-quality fish food from Japan, combined with other ingredients to improve health and color in fish. TDO – A should be offered on or after day 3. You should continue to feed rotifers at first, although you can continue to reduce the concentration of rotifers in the water. When you feed them, you will be able to tell if the larvae are eating the TDO or not. Once it’s clear that they are eating the TDO you can stop adding rotifers to the water.
After about 4 days of TDO – A you can start introducing a mix of the A and TDO – B1. Feed a mixture of both for 3 more days, then feed just the B1 until the fish are about 2 weeks old.
At this point you can introduce other foods such as ground flakes and pellets. The best way to do this is to get a mortar and pestle, which are inexpensive and do the job perfectly. These may be available in local pharmacy stores or online on Amazon (like this one).
As they continue to grow you can introduce larger foods, such as more coarsely ground pellets or flakes crushed by your fingers (about 1 month old). There are also fish foods made for babies and TDO – C2 works well too.
If the larvae are happy with the water conditions and the available food, then they will grow quickly and you should have a quite high survival rate. Regular maintenance will help get the larvae through the toughest part of their growth cycle, metamorphosis.
Baby Clownfish Feeding Chart
| Days After Hatch | Feed |
|---|---|
| Day 0 to Day 10 | Rotifers (can end a couple days early as needed) |
| Day 3 to Day 10 | TDO – A |
| Day 7 to Day 17 | TDO – B1 |
| Day 14 + | Ground flakes & pellets, TDO – C2 |
| Day 30 + | Crushed flakes & pellets, fine frozen foods |
Getting Clownfish Through Metamorphosis
One of the most amazing things about raising clownfish is the transformation from clownfish larvae to baby clownfish. This process is known as metamorphosis, or meta. It occurs around day 10 of the larvae’s life.
Getting the fry through meta is the most difficult part of raising baby clownfish. Once you get past this point it becomes much easier (in most ways).
The key to getting the larvae through metamorphosis is to ensure that they are strong and healthy beforehand and that you give them a clean, stable tank environment through the meta process.
You need to be sure that the tank is clean before the fish begin metamorphosis. On day eight or nine do a good water change, wiping the inside of the tank and cleaning out as much of the detritus as possible. Drip in some fresh, clean saltwater and make sure that your specific gravity is at a good point and stable.
Once you’ve done this you ideally want to leave everything as it is until the larvae have gone through meta and have become baby clownfish. Don’t do a water change. As necessary, drip in either fresh water or freshly made saltwater to keep the tank as clean as possible without shocking the fry by performing a big water change.
You will know that they’ve gone through meta when you look in the tank and see clownfish patterns on most of the fry. Sometimes it’s easier to see these stripes or patterns when looking from above.
Clownfish Growout Tank Maintenance
Once you’ve hatched the eggs, tinted the tank and fed the larvae, the real work begins. If you just left things as they were, the larvae would quickly die.
They need a constant supply of food. For the early part of their life, this comes in the form of rotifers. Even though rotifers are tiny, when you have so many in one tank, plus so many clownfish larvae, the water quickly begins to build up with bad chemicals, specifically ammonia from all the waste.
Beginning on day two at the very latest (you can start on day one) you need to begin adding water to the tank. However, the larvae are very sensitive to changes, so for now it’s best to drip water into the tank.
To do this, I use a gallon of freshly mixed salt water in a jug placed on a shelf above the tank with the larvae in it. Then, use standard airline tubing attached to a rigid airline tube from the jug of water to the tank. The rigid end goes into the jug, and the flexible end gets suspended just above the tank so that it drips into the tank. Use an air control valve, like these from Amazon, to dial in about 1-2 drips per second to start. Over the next few days you can increase the speed that it drips in. But start slowly so you don’t shock the larvae. Do this to slowly bring the water volume from the five gallons you started with until it’s a full 10 gallons of water.
Also starting on the second day you’ll want to begin cleaning the tank. Do a quick wipe down of each side of the tank and scrape the bottom with a plastic scraper (an old credit card would work). Then siphon out all the junk from the bottom. Airline tubing with a rigid tube on one end works well for this too. It’s easier to control than a large tube. You don’t want to take out too much at one time and you want to mostly get the junk out. Sometimes you’ll siphon out larvae. They usually survive this just fine, simply scoop them out and put them back in the tank.
Growing Out Your Baby Clownfish
Now that the babies have gone through meta, you officially have baby clownfish! At about 20 days old they are ready for growout. They should be moved to a larger tank with more room and proper filtration such as a sump with live rock and a protein skimmer.
There is no hard and fast rule for growout tanks. People have had success using everything from bare tanks to full reef setups. The goal is to give the fish room to grow, and clean, stable water conditions.
If you’re going to be growing out batch after batch of fish, then tanks with fewer rocks and decorations are generally easier. However, if your goal was to raise a clutch every now and again, then it is quite an incredible site to see dozens or hundreds of baby clownfish in a reef environment, especially with host anemones. (Clownfish will generally form the symbiotic relationship with anemones as soon as they are past meta, but not before.)
You can mix clownfish to grow them out. For instance, you can mix fish that were hatched on different days, and you can also mix morphs and even species to a point. You just need to ensure that there is enough room to keep the water clean and stable, and that there are enough fish that no one fish is constantly being picked on.
What to do with all of Your Baby Clownfish!
Once you get the hang of raising clownfish through meta, you’ll soon find yourself with hundreds of baby clownfish. So, what now?
The options are basically do you keep them or sell them? Most people have limited space so you can only keep so many fish at one time. Eventually you will probably want to sell some of them.
If they are normally striped clownfish, then your best bet may be to try to trade them or sell them wholesale to local pet stores. Most local stores will welcome healthy, locally bred clownfish babies. But don’t expect to get a whole lot for them. You also may be able to sell some on local online bulletin boards such as Craigslist or local Facebook or reef groups.
Local reef meetings are also a good time to sell a decent quantity of fish at one spot.
If you raise designer types, such as Snowflake or Picasso clownfish, you may be able to get a better price for your babies. You can try everything mentioned previously. In addition, if you have high-quality fish with no defects, you can often sell them online. This is especially true if you’re willing to ship your fish, which is not an easy (nor cheap) task.
Is it Worth it to Raise Clownfish?
Good question. The answer really depends on your goals and aspirations in breeding clownfish. It is well worth raising eggs if you have the desire, time, equipment and patience to do so, with little expectation for selling thousands of clownfish or making it a business. It’s an excellent school or family project and an outstanding learning experience.
If your goal is to create a business or side-business selling clownfish, then you have a tough road ahead. That’s not to say it’s not possible, but unless you have a way to wholesale your clownfish lined up, you will quickly find yourself with more fish than you can sell.
However, raising highly desirable designer clownfish of excellent quality can definitely be a viable business. Just know that it can take years to have marketable clownfish ready and even then, selling isn’t as simple as posting a picture online.
Shipping can also be a nightmare. Clownish must be shipped overnight, which is incredibly expensive and ripe with potential problems. This includes shipping delays, weather (too hot, too cold, etc.), regulations on shipping liquids and live animals, and so forth.
This isn’t to discourage anyone from trying it. The process alone is a worthy challenge and the reward of raising baby clownfish from eggs to mature clownfish is absolutely incredible.