here is a little info on your cucumber. Just a little tip for ya. Anything really cheap at the pet store that is really cool usally won't survive for a very long time. But that is just My IMO. PM me and I will send you some more info on these critters
Even without the Cuvierian tubules and their potent toxins, medusa worms have a variety of distasteful chemicals associated with the skin and body wall to protect them from being eaten by fishes, crabs and lobsters on the coral reef. Although the specific toxins associated with synaptid cucumbers are somewhat different from those of most other cucumbers studied to date (Kuznetsova et al. 1989; Ponomarenko et al. 2001), these animals are still reported to be highly toxic to fishes in marine aquaria if they are seriously injured (e.g., Delbeek and Sprung 1994; Fenner 2000; Michael undated online; Sprung 2001). In general, toxins are only released when the cucumbers are under severe stress (such as being chewed up after being sucked into a powerhead or overflow grate), and a diligent aquarist will usually prevent this from ever happening, and therefore never experience any problems with one of these animals. If however, and accident happens, and the cucumber is stressed severely enough to release its chemical defenses, then a good water change, together with an efficient skimmer and some activated carbon are usually sufficient to prevent any fish from asphyxiating from the soap-like holothurin.
