Breeding Clownfish 2 – Keeping Broodstock in a Reef Aquarium
In the first section of this guide, we looked at an overview of the general process of raising clownfish at home. In the next few sections we will cover broodstock care in more detail, particularly housing, species selection, feeding, and maturation and spawning behaviors.
Most hobbyists don’t get interested in clownfish breeding because they have set out to become clownfish breeders, rather they realize that their clowns have spawned in a display tank and are curious about how to rear the eggs. In this case, the considerations of species selection and housing are already taken care of. As we discussed previously, the young will have an abysmal chance of survival left to their own devices in the adult’s tank. Instead, they will need to be removed to a small larval rearing tank and fed appropriately sized plankton. If you don’t have your plankton cultures ready, don’t despair, well fed and healthy clownfish pairs will typically spawn every two weeks or so for many years to come. You will have plenty of opportunities to try your hand at rearing clownfish.
One of the goals of this series is to pass along the tricks and tips we have acquired along the way to make your breeding efforts as simple and as little work as possible. Here is one tip: When transferring the larvae from the parental tank, there are two methods – capturing the larvae after they hatch, or moving the nest in its entirety just before hatch. If you are just planning on raising a hatch or two, then siphoning or other methods of manual capture of the larvae is just fine. If however, you are planning on raising clownfish on anything beyond a casual basis, it is worth your while to “train” your clownfish to spawn on a removable substrate so you can move the eggs before they hatch.
Training your clownfish to a removable substrate is (usually) a simple endeavor. It can be as simple as putting a 4 inch clay flowerpot or ceramic tile where the egg mass was deposited after it hatches. Often, the fish will take to their new substrate right away, but it may take a few tries of “chasing the spawn” around the tank, placing substrates wherever the breeding clownfish move their spawning site. Eventually they will settle and accept their new substrate. If you don’t like the look of tiles or clay pots in your beautiful reef tank, check with your LFS and see if they can provide you with an appropriately sized empty shell from a Tridacna spp. clam. Clowns love spawning on the concave interiors of these shells and these substrates make for a more natural display. Larval siphoning and egg transfer methods will be described in further detail later.
Nutrition of the adults plays a critical role in the quality of eggs produced and the survival chances of the juveniles. Normally in reef tank systems, the adults have a well-balanced and healthy diet. However, on occasion there will be a nutrient deficiency that leads to poor egg quality. If you are experiencing difficulty in getting eggs to hatch, or large larval die-off particularly in the first 72 hours, adult nutrition should be considered. Supplementing the adult clownfish diet with a variety of high quality foods can be a deciding factor in your success as a breeder. Don’t neglect nutrient export especially on a reef system. Corals will love the extra feedings as much as the clownfish, but a good protein skimmer will help in removing waste products before they can fuel nuisance algae growth.
In the next section we will look at how to set up a dedicated aquarium for clownfish breeding.