Why have my clownfish suddenly stopped spawning?


If your clownfish have been breeding regularly and then suddenly stop, could it be a sign of ill health? Matt Pedersen looks at the possible reasons for them going on strike.

In the wild some clownfish species have breeding seasons and these are thought more likely in those in more temperate/subtropical locations. Wild spawning may also be tied to lunar rhythms.

In captivity it is not uncommon for clownfish to 'go on strike' and stop breeding. Sometimes they will resume, sometimes they won’t. There is no single answer, but here are some possible solutions.

Making a change or disrupting the broodstock aquarium can stop them in their tracks. Rearranging the tank’s décor could be enough. Adding new fish to the tank could also potentially throw them, especially if conflict results.  

Several clownfish varieties and species are typically thought of as unreliable spawners. Amphiprion ocellaris are generally not lumped in that category, but for people with fish like skunk species, including Amphiprion perideriaon, A. sandaracinos, A. nigripes and others, sporadic spawning is almost considered the norm!

As for 'seasonal' breeding, you may have inadvertently given them a cue to stop spawning. A drop in tank temperature could easily slow or stop them. All my tanks run cooler in the winter and spawning behaviour adjusts.

Shortening your lighting cycle could also be an environmental cue to stop spawning.

Other possibilities may include old age, although clownfish can live up to 30 years and I know of at least one 21-year-old pair of Tomato clownfish that still spawn routinely!

Look at their general health and condition. Low feeding levels may have caused them to stop to restore depleted reserves of nutrients required. Actual disease, parasite, virus or bacteria can also stop fish from breeding.

Any one factor could be your problem, so check and rectify. If this doesn’t work be patient, for in clownfish breeding time is the one thing we can’t substitute!