• Looking to buy a cephalopod? Check out Tomh's Cephs Forum, and this post in particular shares important info about our policies as it relates to responsible ceph-keeping.

Need help

Jan 29, 2005
I have a 40 gallon tank that I just took down last night. It was a freshwater tank that I housed two rather large oscars in. I have been looking into getting a saltwater tank and getting an octopus. I have had freshwater tanks for over 9 years. I have a 55 gallon heavily planted freshwater tank. I was wondering what I need to do to house an octopus. The tank is 40 gallons. I have two fluresent 20 watt bulb in a fixture for this tank, would that be enough light, or should I go ahead and buy 2 55 watt cf lights? I have a glass top. The filter that I had for the tank is a hang on back filter (Tetratec PF300 Power Filter). I would like to start putting in live sand and water sometime tomorrow. I read that it takes about 3 months for the water to get stabalized? This seems like a rather long time. I was thinking about getting a large piece of lava rock for this tank and carving out some caves and places for an octopus to hide. Would that be ok or should I buy some live rock. Also are there any kinds of fish that will live in the tank with the octopus or can I have more than one octopus in a tank? I really do not know much about cephalopods but I am going to buy a book and read up on them. I do want to get the water in the tank tomorrow. Any help would be great. Thank you.
:welcome: First!! Second there's a multitude of info on this sit under Ceph Care! Almost all your questions will be answered so please take a look! Also unfortunately, the tank does need to cycle for that long a time so it can become stable and go through it's cycles! Sounds like a great plan as long as you have never had to treat the tank with copper as that is fatal to octopuses and impossible to get out of a tank. Good luck! I am sure you will have many other answers and advise!

:welcome: You've come to the right place for octi info!!

1st suggestion read up well before you get an octi, they can be very sensitive

Yes it will take a minimum of 3 months to stabilise your tank.

Also you say it's been a freshwater tank, have you ever used anything copper based in it?? Medications, ornaments etc etc. If so then I'm sorry that tank cannot be used . Octopus are exceptionally sensitive to copper and it is fatal. It can be almost impossible to remove copper from your system. It gets into the silicon etc.

BUT once you get over all the teething problems and the learning curve, then octis are the most rewarding critters!!!!!

Don't be afraid to post questions we have a whole bunch of experienced ceph keepers here (Nancy, Carol, Colin, Joel.................!!!)


I have never treated this tank with copper. I am going to read the ceph care section right now. If I have any other questions I will reply. Thank you for your quick response.
I,m a newbie to octopi, but not to marine Aquariums....
And even though you say you've never used any copper based medication. It would be a goog idea to test for copper anyway just in case your house has been built before 1950 and full of copper pipes that haven't been replaced.

A good indication of this in freswater usually translates into having trouble keeping fancy plecos, ancistrus,hypancistrus,baryancistrus,cochliodon, farlowella, hypostomus,loricaria, panaque,peckoltia and ...you get the jist...(gist? sorry i'm french)

I think volcanic rock might be a little rough for little octo skin--- go with smoother scleractinia!

I just finished putting in the saltwater mixture I made and the sand in my tank. I measured the tank with a tape measure and then I used the formula to check how many gallons the tank was, because I was not sure if it was 40 gallons or not. The tank is actually 50 gallons. I havent gotten any rocks to put in the tank yet. I was not sure if it would be ok for me to add the live rock to a new aquarium. Plus I wanted to see what everyone thinks I should do as for decor. Pookie said that the lava rock may be to rough for the octopus. I was wondering what everyone else thinks. I know a place that sells huge blocks of lava rock and I had originally planned on carving a lot of differnt places out. I really do not want to use any pvc in my tank. I want it to look as natural as possible. How much does live rock usally sell for?
Also I havent bought a new filter for my tank. I just have the water being circulated with two power heads at the momment. What do you all suggest. I was looking at the price of canister filters, the fluval 304 to be exact. I also looked at some protien skimmers. I have been reading up on some sumps on http://www.kingvinnie.com/aquaria/diy/ but I am not sure what to do. What is the best filtration I can get?
You don't have to use lava rock if you can't afford live rock. You should get some live rock but you can also get some base rock. Look for some that's not rough like lava rock.

even if you try to rush in - you wont be able to... there is an awful lot to learn - are you aware how expensive it can be to feed an octo? live shrimp and crabs are ideal...

A PROTIEN SKIMMER IS A MUST i believe they are great in any tank but for a ceph they are vital - im not an expert by any means on filtration but i have the dreaded bioballs and crushed coral in sump (lookin at reducing the amount) - a diy denitrator - protien skimmer - and am about to install a 3 foot refugium with deep sand bed, mangroves and macro algae... fun fun!

good luck and read - im still a way off getting my cuttlefish after almost a year!!! (my first saltwater tank you see!)
Ok what should I get? I was thinking about getting a fluval 304 and a protien skimmer or building a sump. Would the flubal 304 and protien skimmer be good enough? I am going to order the stuff tonight depending on what everyone thinks, thanks.
Lots of questions...lets look:
Fluval with bacpak or similar skimmer? Fine...with a sump? Better! I like the hang on the back filters and skimmers just fine, and they are easy to keep clean...but a sumped system is better.
Live rock: not a necessity, but certainly the best way to go...should be between 3-10 dollars per pound depending on quality...best bet is to buy some base rock and put some nice live rock on top of it...'
Carving Lava rock: in most cases, this is done with featherock or another of the glass/igneous forms of volcanic rock...BAD idea...the edges are too sharp, and the pockets frequently contain toxic metals and chemicals...DON'T USE IT !!!!!
Let the people who you are ordering from the parameters that you need, I am sure that they will work with you to create the system that you want...keep us posted !
you might have gone ahead already - but there really isnt a great rush to set it up and you might regret it later!!! especially re the filtration - taking the time to set up a sump really well will save you lots of hassel and the hassel of changing over later when you realise they are the way to go... lol my opinion anyway hehe

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