Can I keep a sea apple?


Sea apples are exquisitely beautiful, but not suitable for everyday home aquaria – as Jeremy Gay explains…

Q: Please can you give me some advice on keeping a sea apple in a 270 l reef tank. Will it be compatible with a juvenile Yellow tang, a Scooter blenny, Royal gramma, two Common clowns and a Firefish? The tank is two years old and has soft corals and polyps, along with the usual hermits and snails. Would a sea apple be okay in this tank? 


A: Jeremy advises: Sadly, sea apples aren’t a good idea for three reasons. They are obligate filter feeders, so really need soup-like water, full of suspended food particles upon which they can filter feed whenever they choose. Mechanical filtration, protein skimmers, plus the resultant nitrate and phosphate would make maintaining such conditions impossible in most aquaria. So buy one and it will most probably slowly starve. Next is their dislike for warm water temperatures, with 26°C being their absolute maximum upper limit. And thirdly, and most importantly, their bodies contain poisons that they can release into the tank water when stressed, killing everything — and starvation and high temperatures are just two of those potential stressors. They are exquisitely beautiful, and sometimes offered for sale, but they are really not suitable for everyday home aquaria.