Bad news


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Well, that was short lived pleasure. I'm not sure exactly what happened but my Octo died last night. I checked the water basics and everything was 0, 0 and 5ppm for nitrate. pH at 8.2, temp at 76, 1.023 for salinity. That's all I was able to test, I suspect maybe some sort of metals were present from the rock or something else or I also suspect that the oxygen level may have been too low (too little surface agitation). I feel kinda bad like I wasn't a good owner, but I will try it again. I will be setting up a smaller tank for another small captive raised octo like the one that I had. I'll have the water going through my main display tank (125g) that will help out with any temp or other param changes and make for a better water condition for the next one.

To answer your question angeldust, yes, it was changing colors for camoflage. He was really good at going from the white bottom, the brown rocks and the green plants. Really really cool. Sad for the loss :(
im sorry, i didnt see this post when i posted to the other post, sorry to hear that, i hope mine does not suffer the same fate.
Sorry to hear about your loss. I could have been the result of a PH swing or oxygen drop at night. Cephalopods also like full strength sea water 1.026/36ppt. Did you ro/di water? A refugium plumbed to your tank on opposite light cycles will keep your tank more stable and it is very easy to do. Why do you suspect your live rock?
Once again sorry to hear about your loss, but don't give up. No one ever said keeping cephalopods is easy.
Thanks guys. I suspect the Oxygen could be what it was because there was not much for surface agitation. Water has been RO/DI since it was set up. I suspect the rock because it did not start out as live rock. It was lace rock which I'm told may leach metals, didn't really think of that when I started the tank up a few years ago. I suppose that it could be a possibility. Why would you suspect a pH difference and what would be done to avoid it? Any other suspected possibilities?

Yanni, I'm sure yours will be fine. I think mine would have done much better if I had done what I'm going to do next and just plumb it in to my main tank. That will give a more constant water temp, chemistry, etc. Your tanks are considerably larger than the 7.5 gallons I had mine in.

I value your ideas and instruction if anyone has any thoughts of what might be done better this time outside of plumbing to my display tank. I already have a refugium on that tank, but I'd never see him again if I put him in there, the macros are crazy in there.
OMG I'm so sorry! :(

I hadn't seen this thread until now, sorry for your loss. Hopefully you won't give up and your next little octo will do much better since the water will be circulating through your 125.

Good luck and keep us posted.
The pH shift frequently happens at night. The photosynthetic algaes in the tank quit using CO2 and start burning oxygen, meaning the CO2 levels rise and the pH can shift as a result (like using injection in a FW tank).

Sorry for your loss. I know where you're coming from.
DrMilhouse- how far have you gotten? Has the tank been plumbed to the display?

It wouldn't be a good idea to keep him in your fuge unless it's 100% escape proof.
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I work from 3pm to 6am 5 days a week so I haven't really had the time yet to get it plummed in. It'll take a few weeks before I can get around to it, but I'll bring up some pics when I do.
O.bimaculoides is not prone to escape. As long as water quality remains good, they are well fed you should not have a problem with escape.