The answer to this question depends a little bit on what exactly you are referring to. The number depends on the difference between “tentacles” and “arms” of sea creatures.
Arms have suckers all along the length of the limb, but tentacles only have suckers at their ends. A typical squid usually has 8 arms and two tentacles.
Because of this, you could say either that a single squid has 2 tentacles, or you can use the word “tentacles” in the more colloquial way. If that’s the case, you mean any of the limbs that a squid (or other animal like an octopus) has. In this case, each squid has 10 “tentacles”.
In short, five squids technically have 10 tentacles between them. If you are talking more conversationally, you could also claim that there are 50 tentacles total.
