[Octopus]: Ellen after Harlie

I am thinking of a O.Bimaculoides, but any suggestions are appreciated. I am looking toward something diurnal and larger than a dwarf.
The Red Sea 350 is 75 gallons with a 18 gallon sump. I have the standard filter socks ,Skimmer and loads of Biological filtration media. I have also made a heavy 1 inch thick lid of (I think PTFE ) that covers the entire aquarium quite tightly. The overflow are covered with mesh.
I am thinking three weeks should be enough, but I will wait longer if needed.
The fish will keep me on my toes and support the cycling as I wait to see how the aquarium stabilize.
Things went well with my first aquarium and the two dwarf octopuses, so I don't expect any surprises
The tank is automated using Neptune's APEX system and I regularly use several test kits and biweekly water changes.
I'd appreciate any advice and suggestions, I don't want to make any slip-ups.
Let me know if you know of any O.Bimaculoides, that will be available say in three weeks.
I'll put up some pictures as when the lid is complete.
TomH is a memeber on here who sells Bimacs. He would be someone to watch out for.
Remember bimacs are really a cold water species. It does not kill them being in the warmer end of their tolerance, but it will shorten your time with them.
They can still get pretty good size though I will attach a photo of a former one I had for size reference.
I think a bimac or a briareus would be appropriate for that size. Remeber anything that is potentially food for the octopus can be eaten. So fish and some of your clean up crew species will be canon fodder.
If your system is within safe parameters. That is your call. If you have a good skimmer that will help with oxygenation. A lid that is not heavily vented will help with evap and salinity changes. The ph needs to stay within a certain range.
Those are my 3 personal fundamental requirements for the animals well being.
Obviously a proper nitrogen cycle needs to be established. Test your ammonia and nitrite for another week to be safe, if no changes happen then you should be good to go. I personally think you would be ok. Bimacs aren't cheap so if you want to take the time though, it is not going to hurt.
They are pretty tough animals by the way. If you can keep a simple reef tank, then it should be easy. They can handle sustained levels of ammonia up to .2 If you ever see that tiny spike don't freak out to much. The lowest ph tolerance is 7.5, but never! let it get that low, that could be a sign of a problem with your system. I recommend testing ph daily in the evening after or right before lights go out. After some months go by and you notice a stable ph pattern then You can start doing it less frequently.

If you start training an octopus to open things, make sure to use plastics that have a recycle symbol with the number 5 in it. That means that plastic is aquarium safe. There are other safe plastics though.

The picture attached is of jolene. Her mantle was bigger than normal do to it being close to egg laying time. With female bimacs (and other female octopus in my experience) you can actually see growth like a pregnant womans abdomen.
The aft end of her mantle will start getting bigger.
If you can identify their branchial hearts the two dark spots close to the end of the mantle. When it gets closer to egg laying time you will notice a definite distance change of those spots from their position to the end of the mantle.

Some of this information won't necessarily be helpful but it is here now. If you get a male that is a different story.


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Thank you for the your helpful reply.
At the end of the 25 day cycle the values are pH 8.4, NH3 0, NO2 0 NO3 30 and Salinity 30.0.
I have been keeping the pH at 8.3 and the Salinity at 31.0, so there is still some adjustments needed.
As for the fish, I'll keep a record of what the octopuses preferences are.
I feed the dwarf octopus one Fiddler crab every other day. I enjoy seeing Helen do her stuff.
I don't know how much about a Bimacs dietary needs are, I am looking forward to finding out.
The first dwarf laid eggs, this was exciting and very rewarding.
A bimac will eat well on live crab and you can buy frozen shrimp from Walmart. I mainly feed mine those peeled raw shrimp from the freezer section. They are pretty cheap. I have also fed one squid, chicken, and frozen crab. Feed them once a day. Wait for them to be active though. Go in and start interacting. Then give them some food. Krill was not accepted by Jolene so I never tried with Snips. So keep that in mind.
Your salinity needs to go down... I think the ph too.
Other than that. You are good

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