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, it’s not as easy as it might seem. There’s a lot of setup that goes into successfully hatching clownfish eggs and a lot more into raising the fry. At the same time, clownfish are one of the few salt water species that amateur fish breeders have had a lot of success in.
Collecting Clownfish Eggs
As mentioned in our How to Breed Clownfish article, you can either let the pair breed in your display tank or you can set up a separate breeding tank for them to spawn in.
If you have a separate breeding system, then the best option from those below is number 1, where you remove the eggs before they hatch. If that isn’t possible for whatever reason, then number 2 could work as well.
If you plan to let your clownfish breed in the display (or if they already have), here are the options.
- You can try to remove the eggs before they hatch. Sometimes they’ll lay on a rock or something that can be taken out of the tank. In this case you’re in luck! Just take it out of the tank to hatch the eggs. Otherwise, you can try to put something in the place that they lay the eggs in hopes that next time they’ll lay it on the pot or tile or rock that you put in place. Small 4×4 or 6×6 inch tiles work pretty well for this.
- You could let the eggs hatch in the tank. The biggest drawback here is that it’s extremely difficult to collect the larvae once they’ve hatched. You need to be there when they do and you need to turn off all the pumps so they don’t immediately get killed by powerheads or pulled into the filtration system. From this point there are a couple of options.
- The eggs will hatch within a couple of hours of the lights going out at night. So you would need to wait until the lights are off, then turn off the filtration and wait for them to hatch (be careful not to leave everything off too long or you could do damage to your tank!). Once they begin hatching you need to try to gather the larvae in one area of the tank using a flashlight. Hold it right against the glass near the surface of the water. Once you get some larvae gathered here, gently scoop them using a bowl or some sort of container. Do not try to use a net! Then move them to the growout tank, which you should have previously set up.
- You can use a device such as a Vossen Larval Trap. This ingenious device safely captures the larvae after they’ve hatched so that they can be moved to a rearing tank. See it in action below:
When Will the 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 a number of factors, including temperature of the water and species.
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. So if you get a first clutch of eggs and by keeping careful track of the progress, find that they hatch on day 7 after being laid, then you can be sure that the eggs will always hatch on day 7. Again, this assumes that everything else remains the same.
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 the vast majority of the eggs are silver and you can see their eyes inside the eggs, then they will likely hatch that evening.
Before the hatch
Prior to even thinking of raising clownfish from eggs, you must have live food for the larvae. In the wild clownfish larvae will eat plankton and other nearly microscopic plants and animals. In captivity, by far the most readily available food for clownfish larvae is 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.
Clownfish eggs always hatch at night. 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 completely darkness, so not a busy room where people will be popping in and flipping on the light.
On hatch night, the tiny fry will emerge from the eggs usually within a couple of hours after the lights go out.
Hatch or Rearing Tank Setup
Getting the clownfish to hatch out and through metamorphosis is by far the most difficult part of raising clownfish. And 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 ten 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, but just make sure to use very hot water and clean thoroughly. Do the same with everything that goes into the tank.
You’ll need a heater (100 watts works well), a thermometer, an air stone and a sponge filter to go in the tank. The sponge filter should be seeded for at least a week in the brood tank so it collects some of the beneficial bacteria. This does not need to be cleaned. Have a few 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 brood tank and make sure that it can hold the temperature stable. Also, use black electrical tape to black out the small light that turns on when the heater is on. If not, 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 3 sides (leave one unpainted), with construction paper or cardboard, or as I used, insulated wrap like this. You don’t have to use that, I just did because I thought it would help keep the temperature more stable.
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 the 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 very dim. Too much light can actually cause the fry to die.
For water, I put 3 gallons of freshly made water into the tank, making sure the specific gravity was the same as the brood tank’s. Then I took 2 gallons of water from the brood system and put that in the tank. I did this all on hatch day, giving the water temperature enough time to stabilize before the lights went out.
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, make sure you’re ready before the normal schedule. Have the water in the tank with the temperature stable and the air bubbler running (the sponge comes later).
About an hour or so before lights out, move the eggs from the brood 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.
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.
Once everything is set in the tank, the air bubbler is running over the eggs and you are otherwise ready, just wait for the time when your brood tank’s lights turn off. 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 2 options at this point. You can check everything in about two hours and set up the tank for all the larvae, or you can wait until morning to do this. The larvae will be able to survive until the morning with the egg sacks, but I usually did everything about two hours after lights out. In that time most of the eggs should have hatched. However, if you see that a lot of eggs didn’t hatch then you might want to wait until morning.
You don’t want to bust into the room and turn all the lights on. You can literally scare the larvae to death if you suddenly turn on lights. It’s best to check with either a very dim flashlight, or if at all 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!
Either way you decide to go, when the eggs are done hatching you are ready for the next step. 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 of the eggs to hatch. The pot can be cleaned for the next clutch now.
Now 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 the algae really well in there, and quite heavy, 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 green. You want it dark 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.
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 there 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 all 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.
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.
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 2 at the very latest (you can start on day 1) 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 used a gallon of freshly mixed salt water in a jug placed on a shelf above the tank with the larvae in it. Then I used 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 slow so you don’t shock the larvae.
Also starting on the 2nd day you’ll want to begin cleaning the tank. I usually did a quick wipe down of each side of the tank and often would have to 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.
Feeding Baby Clownfish
As mentioned, newly hatched larvae need rotifers to survive. In the wild they do not eat rotifers, but they eat the plankton and micro-organisms that occur naturally in the ocean. Since we can’t easily recreate this plankton, we use rotifers.
There is no other easily attainable alternative for clownfish larvae food. They will not eat dry foods when first hatched and other live foods such as freshly hatched brine shrimp are too large for newly hatched clownfish.
The larvae will need to have a constant supply of rotifers for about the first 10 days of their lives. On about day 5 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 begin introducing 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.
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 point 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 ensuring 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 start meta. On day 8 or 9 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 a big water change.
You will know that they’ve gone through meta when you look in the tank and see clownfish patterns on the majority of the fry. Sometimes it’s easier to see these stripes or patterns when looking from above.
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 ever y 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.)
What to do with them now!
One you get the hang of raising clownfish through meta, you’ll soon find yourself with hundreds of baby clownfish. So what now?
Well, 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 type clownfish, such as snowflakes or picassos, you may be able to get a better price for your babies. Again 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 no easy (nor cheap) task.
Is it worth it?
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. Your 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 worth challenge and the reward of raising baby clownfish from eggs to mature clownfish is absolutely incredible.