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SOme info on octos


Mar 30, 2003
I have been reading the threads posted on octos and have been doing a little homework on them and i really want to give it a shot. I have heard mixed reviews(even my mother is trying to perswayed me in the other direction) about octos but want to do it. My 55g has been up for about 8-9 months now. I have a few questions:

1. Will my emporer 280, millineum 2000 and seaclone 150 protein skimmer be good enough filtration?

2. Is 190 watts too much lighting for him?

3. I have 4 corals; Brain, toadstool leather, frogspawn and a hammer head coral. Will they be alright with an Octo?

4. Since all my filtration means are hang-ons, will it be difficult to "seal" up the top on my tank?

5. I have heard some sites say that Ro/di water, what exactly is that?

Those are a couple more than a few, sorry about that, just want to make sure everything is right. Thanks again for the help.
I can offer up a couple observations...

General opinion is that 190 watts would be too bright...not that it directly harms an octo, but that it causes them to hide and may stress them out. This is an issue I'm struggling with myself, since I want nice corals as well and currently have 220 watts. I'm thinking of arranging one or two nice, large, shaded rock "caverns" beyond what already exists in my live rock.

I'm also struggling with the top seal issue. With my former, now sadly deceased octo, this was not an issue, but most specimens need some escape-proofing. My best theory at this point is to cut a more precise plexiglass top and/or dream up some sort of barrier system...I have heard that octos can't stand or perhaps can't attach to astroturf.

RO/DI water is Reverse Osmosis or DeIonized water. Or, in the best systems, both. Tapwater added to an octopus tank isn't ideal...you really want to purify it. Lots of ways to do that, but Reverse Osmosis and Deionization, especially used in combination, are by far the best. They are, however, expensive. Some folks can get away with even tapwater, their local water is so clean! But that's absolutely not true for everyone. I've had success with a very cheap homebuilt system using carbon filtration and a PolyBioMarine filter. I'm hoping to cobble an article together about that for Tonmo, but I've been lax in working on it lately... :oops: Even so, my system can't get everything RO/DI gets, and I don't have hard data on what it DOESN'T get, so I really can't say if it'd pull out octo-harmful contaminants for all users. For all I know, my tapwater may just be excellent to begin with.

Hope that's a little helpful...

Hi bigvfb12 welcome to Tonmo;

1st yes the Emporer filter is a great one to use as it is 3 filters in one mechanical (filter pads) Chemical (activated carbon) and biological (bio wheels) The protien skimmer is big enough I am not familar with the millineum 2000 filter but it would help out.
If you are keeping corals then the octo would be quite happy in the same water conditions as both octos and corals are very simalar in water quality issues. The lighting might be a problem however as they do not like light. I have a small tube atop my tank for him and that is it. Like rrtanton said he would probably spend much of his time hiding as octos are nocturnal hunters. There is no reason why if when you turn the lights off at night though that he would not come out and hunt. You just wont see him during the day.
As far as escape proofing the aquarium I have used fiberglass window screen to seal off the tank the returns into the tank from the filters can just go through the screen . You will need to seal off the tank, you know the saying "the grass is always greener on the other side" it applies to octos too. Make a plexiglass lid that completely seals off the tank with window screen for the returns if you can use hot melt glue (the low temp stuff) and seal the screens around the filter so there is no escape. I use a weight on the acess doors of my tank so the octo cannot lift it open and get out.
If you are still interested please feel free to contact me and I can provide pics, drawings or anything else to help. You will enjoy an octo more than anyother pet you have every had, promise.

Pacific Blue :boat:

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