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Cycling Fish


Larval Mass
Mar 27, 2004
When I'm cycling the tank for 4+ months, what kinds of fish/anything else would be good to use in cycling the tank? I would prefer them to be something I can keep in the tank with the octopus because I don't want to have them get eaten, bug the octopus, and/or have to get another tank for them to be seperate from the octopus. Thanks for any replies.


May 15, 2003
:welcome: to TONMO.com LNell!!

Afraid there's very few fish which can be kept with an octo that doesn't get eaten, harrasses the octo or gets eaten in turn. Even sharks have been taken by octos!

People have tried seahorses, damsels etc..., for some it works out, for others it doesn't. Its best for the octo to not have cohabitabitants.We recommend mollies to cycle the tank, they can be taken out easily once the cycling period is over unlike most other fish


TONMO Supporter
Nov 14, 2002
either that or cycle the tank with a couple of bits of live rock and maybe a couple of urchins, avoid the spiney types...

Most fish will be eaten, the ones that won't will eat the octopus.

Avoid inverts with sharp spines.

All crustceans will be eaten.

Avoid any anemones as they will sting the octopus's sensitive skin.

I think that using mollies which are bought and acclimatised to salt water over a few hours are the best idea, they can be easily caught when the cycling is over.

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