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Starting an octo build, can I get some advice?

O. Joubini seems really tiny to me but I'll see what happens once I get the tank set up. I came across a 70g half hex type tank today but it has no stand and it's drilled. I would really like to go the aio route if I can but maybe that won't happen. We'll see.

The last of my corals were sold out of my 18g today so I just need someone to come get the tank.

Any ideas about putting feather dusters with octos? How are sponges and gorgonians with octopuses? I found an amazing source for macro algaes so I'm really excited about that. Oh and it seems like base-type live rock would be better than the really branchy stuff as far as dens go. Is this correct?
Any ideas about putting feather dusters with octos? How are sponges and gorgonians with octopuses?

They should be fine just make sure you secure antthing you put in there well. Octos can be kind of destructive when crawling over and aroyund stuff like sponges and gorgs.

Oh and it seems like base-type live rock would be better than the really branchy stuff as far as dens go. Is this correct?

Base rock is standard but there is no reason whty you couldn't have a few branchy pieces too. but you definately want to make sure there is some good caves and hiding spots.
Off the top of my head lists of what I normally keep I put in my octopus tanks (keep CaptFish's warning in mind while placing anything as octos just crawl over whatever is in their way), what I have seen successfully kept, what is likely to be OK from observation and what to avoid.

My List of Successful Occupants

* Brittle stars - great choice, great cleaners. I keep one red one in each of my octo tanks. Both these and serpents can be hand fed if you feed daily at the same time.

* Serpent Stars - another personal favorite housed with my octos. Avoid greens as they will become aggressive once they are a few year old, personal verification

* Caribbean Common Starfish - not a problem with octos but even large tanks have a hard time supporting them food wise (anticdotal, they my just get old and shrink after several years as I can't seem to verify the natural lifespan).

* Most Gorgonians - They need high flow areas. IME these do well in the larger tanks (50+ gallons) but not as well in the smaller.

* Mushrooms - Getting them to attach is the only problem, the red ones from the Caribbean seem to be octo-proof and have stayed in place even when senescent animals have worked at trying to remove them.

* Leathers, Xenia, Kenya

* Feather Dusters - place where they won't be molested.

* Low Stinging Polyps - It is hard to know the impact of the polyps, if you add polyps observe the octopus. If it touches the polyps and reacts by quickly removing the arm, take out the cluster before it spreads.

* Common Clams from the seafood market - These are not pretty, might help filter your bottom substrate, are hardy and may ocassionaly go missing - as in eaten. They are a lot of work for the octopuses and when octos know there is easier food, mine have ignored them. If eaten, they are far less messy than oysters or muscles and I have never had one detectably pollute a tank. Forget any kind of attractive clam, it will not survive.

* Peppermint Shrimp - I have found that starting with a pair before there is an octo in the tank and then introducing an octopus usually lets me have one shrimp over several octopuses. Anecdotally, it appears one will observe the other being eaten and then learn to avoid the octopus. The reason one survives and the other is eaten is conjecture but I have experienced it more than once. Peps are not particularly attractive - almost creepy - but will help keep some forms of small aiptasia from heavily populating a tank. They don't seem to like the larger ones and some varieties but for the ones they will eat, they do a great job. I don't recommend keeping more than two in a tank because they can pack and become aggressive. I have seen them try to pick on an octo but that is usually short lived and only during acclimation or when an octopus is dying.

* Snails or Hermits - Add a handful or more at a time. Some will become food but they make a decent clean up crew. Typically, I will keep one or the other but often keeping both eliminates the snails. I often wonder if the reports of octopuses eating snails is actually consumption by hermits.

* Pencil Urchins - Good rock cleaners but they will munch on some forms of soft coral if there is not enough algae.

Usually OK List(animals to watch because of water quality but won't harm the octopus):

* Cowrie - (I keep one in one of the 65's and am very fond of it. Joe-Ceph reported a major problem with one sliming and I did have some slime the first year I had this one but no problems at all since and he has been kept with numerous octopuses.

* Cucumber - I have not kept a cuc in with my octos but many have. Keep away from the exotics as many are responsible for the infamous cuc nuke syndrome but the commons are harty and don't seem to pollute like the exotics even when they do die. I recently had one to find a power head intake in the sump or our nano - obviously he should not have been IN the sump - and mutilate the animal but the tank did not suffer. There is at least one from the Caribbean that don't bury and are enjoyable to watch.

* Low Stinging Anemones - I hesitate to add this one and don't keep them with mine but a couple seem to be tollerated in a larger tank. Typically these will sting if contact is made and stings can damage the skin, setting up a potential infection.

* Ricordea - these do have a slight sting and should be used sparingly and in places the octo would not typically travel. I have only kept one ric and one flower with any of my octos. The small ric does not seem to be a problem but I have seen Diego react strongly to the flower (it was in the tan before he came and removing it would mean killing it so I am monitoring).

* Pincushion Urchins - There are warnings against using this kind of urchin but I have seen many people keep them in an octo tank without a problem and suspect the warnings are unfounded. However, I do not keep them with my octopuses

Avoid list most anything not listed above but especially:
* Any kind of fish. Sooner or later one will be a problem for the other.

* Seahorses. Guaranteed meal, they have no defenses and even if not actively attacked will ultimately be touched and then consumed.

* Long Spined or Rock Urchins - the spines on these break and embed easily and can be another source of unnecessary infection risk.

* High Stinging Corals - the list includes most hard corals and anemones.

* Aggressive Sea/Serpent Stars - Green brittle star and any meat eating star that can trap its prey. Anticdotally, we may have lost one octo to a Bahama Star that trapped and killed a sleeping octo. It is possible that the apparently healthy animal died and the star was scavenging but I keep it on my no list because of its behavior.
I read through that article but I didn't read the thread. Thank you for posting that.

Does anyone consider rhodactis mushrooms to have much of a sting? I would like to do a ric garden but if that's not a good idea I can use other mushrooms. Oh and does any one know about conch snails and larger turbos?

Thanks for the advice so far!
LOL, the things I keep in my tanks post was written FOR your request but CaptFish copied it to the other thread for safe keeping :biggrin2: (thanks again capt).

Most mushrooms fall in the OctoSafe category but exceptions can always exist. ANYTHING you put in an octo tank and then observe the octopus touching and immediately reacting to should be removed (doubly so if it multiplies easily). I avoid zoanthids for this reason. Many do sting and even if it does not sting YOU, it may effect the skin of an octopus. The easiest way to ensure success is to plant the stationary creatures on their own smallish, removable rock and then arrange the rock in the aquarium. With a single aquarim this is somewhat difficult but breeder nets can be used to encourage attachement and are only ugly for the time it takes to get the animal to attach well (roughly 2 weeks). That is, IF your octo will leave the net alone :biggrin2:. A breeder net can also be useful if you find the animal unsuitable for the primary occupant and you need to keep it for awhile until it can be sold or traded. If you have enough space (not likely) when you build out your AIO, the sump compartment can be used this way too but usually the equipment will need all the room. A remote sump is usually handiest and won't impact visuals.

With the exception of cone snails (some being dangerous to humans as well), I know of no commonly available snails that are problematic FOR the octopus. Do note that they may become dinner but we typically see them survive (more so after an octopus is accustomed to a regular, easy meal). OhToo worked very hard on a turbo he found in his new tank and I was sure he had eaten it but if you will look at the series of three stills (videos no longer available) here you will see that the snail survived the attempt.

I have not tried any of the smaller conchs with the octopuses I have kept. "It is well known" that octopuses eat conch in the wild but so much is species dependent and not noted as such it is hard to say. I do know that the three animals we have tried offering conch meat to declined. If you choose to experiment, try an interantional food store for live conch. Be sure the animal is alive when you buy it (my first attempt at bringing a live one home taught me to check more carefully and is the reason we had fresh conch meat to offer. My original purchase intent was to see if I could keep one alive in a non-octo tank. My second attempt is still alive after several months).
Oh I didn't realize that. Thank you! Well I'll start with mostly mushrooms and what happens. I really like palys and zoas but I can live. Experiments await me I guess.

I found an acrylic tank that I may try to buy if my current equipment ever sells. It's about 75 gallons and it has a false wall on the back that I can use for filtration and all that fun stuff. I won't be adding a sump because of the water damage issue in this apartment but it is drilled so I can consider it in the future. Sound a bit better than the 55g? :smile:

In other news the octopus we have at the store has made friends with me, his new owner has not come to pick him up yet (which I'm not too pleased about) so we've been trying to get him used to people. He actually reached out to touch me yesterday. Some day I'll get some photos for you to identify him but I'm not too worried about it at the moment.
He actually reached out to touch me yesterday

That first reaction and the resulting attachment is what I call, being touched by an octopus. Some people :wink: get hooked that way. They are not all interactive and some are more memorable than others but with each one, the first tentative touch is always exciting.

The acrylic sounds great and forward useful for expansion with a sump. It will also help with your weight concerns because it is light enough for you to lift by yourself (don't try it though because of the bulk) and leak concerns (they don't split or leak at the seams if they hold water initially). Do be aware that if is badly scratched, you will have a two week, not one day, project if you choose to remove the scratches. It is true they can be buffed (with good results) but the actual buffing is a long process that you cannot shortcut (you will "scratch" the tank in a much larger area initially but ultimately it can be buffed to close to new condition). Cleaning is another concern because you can't use a metal scraper and you need to replace the blade frequently on the plastic ones (if they chip, you will scratch the tank). I have both and see benefits to each. One of the things I like best about the acrylics is the flexibility and only my upgraded from acrylics have been reused as sumps.
cadre;178621 said:
I found an acrylic tank that I may try to buy if my current equipment ever sells. It's about 75 gallons and it has a false wall on the back that I can use for filtration and all that fun stuff. I won't be adding a sump because of the water damage issue in this apartment but it is drilled so I can consider it in the future. Sound a bit better than the 55g? :smile:

You're probably talking about a "uni-quarium". Because the back compartment was (probably) designed to hold bio-balls, most uni-quariums were used for fresh water, so there's a higher chance that a used uni-quarium was exposed to fish medication containing copper. Copper is so toxic to octopus that most of us are afraid to use a tank that has ever been exposed to copper, for fear that the acrylic or silicone (or glass?) may leech enough copper into the water to kill an octopus, so try to verify that copper medication was never used. The fear of used tanks that were exposed to copper may be very legitimate, but it may also be exaggerated or unfounded. When an octopus dies for no visible reason, after living in a 2nd hand tank, copper is suspected, but I don't know if anyone has ever deliberately put an octopus in a tank that they know had been exposed to copper, to test the theory (ethical issues). So try to verify that no fish medication has ever been used in that tank, and if it has, try to verify that it didn't contain copper.

I agree with what D said about acrylic tanks. There's also no greenish tint as there is with thick glass. Another difference is that the bottom of an acrylic tank must rest on a strong, rigid, flat surface, where as a glass tank only needs to be supported on the edges, so be sure to get a stand with a flat top.

Oh, remember that the volume stated for the uni-quarium is sort of a lie, because they use the outside dimensions of the whole tank, including the rear "sump" section, to calculate the stated volume. so if the outside dimensions are 48"x18"x20", they would call that "75 gal". At 231 cubic inches per gallon, and assuming 3/8" thick acrylic, and a 3" wide rear "sump" area, the main tank will only hold (47.25 * 13.875 * 18.75)/231 = 53.2 gallons. Plus whatever water is in the rear section, minus the volume taken by your sand and live rock, so call it about 53 gallons of water net. That's how much water is in my bimac system (also no sump (to help keep heat out)) and the species you plan to keep are a bit smaller than bimacs, so you should be okay if you don't load the tank up with live rock, or stinging anemones that take up space the octopus could be walking around in. I still like the idea of partitioning off the end/side of a rectangular tank, giving the octopus a closer to square living area, rather than a long narrow area, but if it falls in your lap for cheap, it doesn't make sense to modify an existing tank yourself.

As far as leak protection goes, I think you're smart to want to avoid a sump if you've got downstairs neighbors. Acrylic won't break like glass can, so you'll be close to zero chance of a leak. Short of an earthquake tipping the whole thing over, I think you'll be covered.
Hm, this may well be a uni-quarium. The current owner used it with a reef system so I kind of assumed there was no copper used in it but I will ask when we look at it today. It is very scratched though so I have a lot of work ahead of me to polish it up. Oh and it is a very odd shape so a custom/homemade stand will be in order. It seems like the best option for the price so I'm okay with putting in some work for it.
Ask the current owner if he bought it new, or used. If new, and it was a reef, then you should be okay with the copper. If used, then who knows, it's a dice roll (maybe not worth the risk?).

You say it's "very scratched". How much more would it cost to wait for a used acrylic tank that is the right size, but not "very scratched"? I polished the entire front viewing area on a 90 gallon corner tank, and it was so much work and time, that I would never consider doing it again. I used power tools (air powered jitterbug sander) and did it wet (so air instead of electric power) so that I wouldn't have to breath the fine plastic dust. there were a lot of medium depth scratches, so I had to sand down a lot of plastic, and then buff out the now "cloudy" surface with a fine grit rough. It took so many hours to safe the price difference between that tank and a less scratched one, that I was probably working for less than a dollar per hour. Never again. If I had to do it without any power tools, just elbow grease, I'd happily throw the tank away, get a second job, and earn the money for a new one (or a used glass one without scratches. Buffing out a few light scratches is not that hard, but buffing out a large area is grueling. Fair warning.
I asked and it's always been his tank, no copper. The tank has quite a few scratches from cleaning with the wrong things. They aren't too deep and I plan to use power tools so oh well. Acrylic tanks do not go up for sale around here very often and then they do they are expensive so if I don't use this tank I am stuck with the 55g. I already have two jobs and I still have no money, I have yet to get pay checks from either since I just started. No extra money but I do have some extra time until my classes start in August.
If you've got more time then money, then it makes sense to buff it out, especially if you have the right tools, and such tanks are rare where you are.
One tip:
I may have created a lot of extra work for myself by creating more scratches. My first pass was with a jitterbug sander and some very fine sand paper, and I made the mistake of letting a piece of sand or some other particle get between the sand paper and the acrylic, and it scratches thousands of little circles into the acrylic before I realized it. They were faint, but they were everywhere, and it probably took a lot more work than would otherwise have been required to remove both the preexisting scratches plus all the little circles that I scratched in. So be very careful not to let any specs of anything hard get under your pad, and wash off all dust and abrasive completely each time before you step down to the next finer abrasive. Acrylic is rather soft, and so a speck of anything harder than acrylic can create new scratches (and make you need to start over).
I totally agree with Joe-Ceph about being as careful a possible to keep from adding scratches while you sand but be aware that even a small scratch (particularly a deep one) will mess up an area much larger than the size of the scratch by necessity since you have to sand the scratch(es) down to even the acrylic. It is a LOT of work but I put a terrible gouge in my tall tank (and almost pulled it on top of me) once and lots of patient work left it where you cannot find the mark years later. Now the inside is so scratched from cleaning that I would not consider redoing it but I have no intent of eliminating it either.

Acrylic will scratch from moving LR around in addition to using chipped "acrylic safe" scrapers (or getting grit under a sponge) so some scratching is unavoidable. The worst usually occurs when you are arranging the tank so if you can place something in front of the front and sides, you will minimize your initial damage.

There is no evidence that acrylic absorbs copper like is suspected of silicone and I have used several well cleaned FW acrylics with no issue. However, I don't KNOW that copper was ever used in them.

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