This a fish market they are temporary closed due to gas problems but there's another fish place on 125th between Amsterdam and Broadway just like this one they stay open 24hrs for those who don't mind traveling
They're temporarily closed not sure when they reopen, but I've never seen octopus on menu, clams yes, there is another place right at the corner of 3rd ave 110st next to Pee Dee steak house and i know they have octopus, also you can pick out your food and they steam it for free, also they have fried fish, shrimp, onion rings and so on pretty good food and prices.
This is a fish market, you can buy fresh and frozen seafood, I'm not sure about clams and octopus specifically.
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