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I made a HUGE mistake! Please help me fix it!


Jul 11, 2003
Stupidly i filled up my aquarium with tap water (i know i feel like an idiot) and i bought a 20 gallon tank instead of a 30 gallon tank the guy told me that if i wanted to get a 30 gallon tank it would cost me around 1000$ as aposed to 450$ Is there ANY way that a bimac could live in my tank?

If it is possible to keep a bimac in my tank would i need a protein skimmer?

I thought i should drain my tap water and fill it up with RO water. Would this do anything bad to my tank or fish somehow? and if i can do this should i leave the substrate and rock work in there?

Also, i would like to know if im going to need a heater or an air pump?

What temperature does the tank need to be?

Also, the guy gave me this stuff called "cycle" it is said to "keep aquariums healthy and rapidly mature new aquariums." He told me to put half the bottle in at first and then 2 tsp daily. Should i use this stuff?
Hi Rockthis,

I'm going to leave a lot of your questions for Colin or someone who has direct experience with some of these things like the cycling chemical.

Is it possible that you could return the tank? In Texas you have three days to return just about anything - I don't know where you live or what the laws are there. I think you can get a 30 gallon setup for a lot less than $1000 if you're careful and patient.

A bimac grows large - you need at least a 30 gallon tank. You could have a pygmy (dwarf) octopus, or you could have a 20 gallon reef tank and learn to keep a salt water aquarium and then get another tank.

I know all this is complicated, so I wish you the best in working through it.
ok il just wait for someone else to answer. It is possible for me to get a new tank, am i going to need a protein skimmer for my new tank? and what kind of filtration should i use?

p.s sorry for the never ending questions

you getting yourself in a mess eh? :biggrin2:

Okay, i think you fell for some sales patter but we can get through this ( i only have 5 mins this morning before i have to head off to work but will get back on later (8:06AM my time just now)

If you want a bimac, the tank is going to be too small, that's a fact. No other commonly available octopus is going to live up to a bimac so you are going to need to get a biger tank.

The tank should have been up an running properly for probably about two weeks before you added just one fish!!! As you have set up and added fish at the same time, its probably going to be bad news for the fish. The tank needs to mature BEFORE anything living goes in.

Yes you will need a skimmer, especially in a tank that's in the smaller category.

There is no way that increasing the tank size by 10gal adds $500 odd dollars! This guy is scamming you for a quick sale if that is what he quoted you.

In fact. if this LFS knows that you are setting up your first tank he should be ashamed of himself! :x you need to take the fish back immediately and I'd get my money back! Give him back the whole thing, actually. It's all been bad advice from him and you have an unworkable system. The fish will die because you have no system set up.

This isn't your fault, an LFS should be guiding you better.

I need to go, but i hope some others may add to this, dont panic, but I'd make arrangements to get those fish back to the shop as soon as possible, its a waste of life (and money)

sorry about all the hassle you are having
Thanks alot Colin :notworth:
Id take the fish back this second if it wasnt 12:30a.m right now
Should i get new live rock?
and should my new tank be 30 gallons? or should i go for bigger? (im worried if it is really big it will be to hard to take care of)
Any other help would be GREATLY appreciated (i dont want this to happen again). I got myslef in a real sticky situation and i need help out of it.

P.S thanks so much i know u were pressed for time so i appreciate u answering. Maybe when u get more time u can help me out more, maybe answering some more of my questions :mrgreen: :mrgreen: :mrgreen: :mrgreen:
RT, I am a little confused...how in gods green earth did someone say that a 30 gallon tank would be 1g$ ??? A fifty five sells for 60 bucks new out here in AZ, and even with all the stuff, it would come in at under 600...it sounds like you may have been ripped off. Take back everything, call the better business bureau, and find another store!
I think that a bimac would be happiest(and longest lived) in a tank exceeding 40 gallons...55's are an industry "standard" size, and are usually on sale somewhere...right now, Petsmart has them for 49 dollars...this just includes the tank and a glass lid, of course, but from there you need a power filter (100.00) and a bac-pack (about 200) some live rock, and you are set!
You are definitely going to need a protein skimmer...the bac-pack is the easiest to use for a hang-on-the-tank sort, easy to set up, and easy to clean out...I prefer the sump system myself, but that is (pardon the pun) a whole different kettle of fish! :lol:
Don't let this whole affair get you down...it sounds like you have all the required enthusiasm to be one great ceph keeper, and we can all hardly wait until you have a nice big bimac to send us pictures of...good luck, and keep the questions coming...that is what we are here for!
thanks so much everyone i wont give up.
My dad went to go take back the tank and we are getting a 40gallon one, its not here yet (but when it comes im gonna rreally need some help in cycling it RIGHT) thanks again
I forgot to ask one little thing. The guy gave me an "aquarium power filter" called "Aqua Clear 3000" will i need to keep this if i get a protein skimmer??
Hi Rockthis,

I'm on the boat with those who are saying you got royally gypped by that LFS. You can build a perfectly serviceable octopus tank for a fraction of what they were saying.

I set up my first octopus tank, with world reknowned Jimbo Octopus Life Support System Mk I about 9 years ago on a budget of less than 300 bucks, and kept my first bimaculoides happy, safe and sound to a natural death. That tank was the following:

30 gallon tank.
Fluval 450 canister filter
Seaclone Skimmer.
Regular tank stuff. (10# live rock, gravel, things to hide in/play with, thermometers and test kits, etc.)
I built my own lid and stand.

For a cephalopod, a skimmer is not optional, and you should spend the money to get a good one- not one of those $20 bubblestone models.

When selecting a tank for a cephalopod, look for something with a big footprint- a typical 55 gallon tank is long and tall, but narrow. It's good for displaying fish and other swimming creatures, but all tankbound cephalopods are sea floor-oriented wanderers- and will benefit from having a lot of "sea floor" in their tank.

One last word about tank chemistry. With the exception of getting liverock, gravel, or filter media from a tank that's been established a long time, there is no product on earth that can accelerate the nitrogen cycle. The home aquarium industry thrives on bogus products promising enticing benefits for people's tanks, but to the scientifically oriented folk, it's a lot of hogwash. If nitrobacter genus bacteriums could live in a shelved dark bottle of water in concentrations that could immdiately benefit a 30+ gallon tank, this stuff would live in everything- including our tap water. Truth is, it does. It also lives in your body, on your clothes and in your garbage disposal- in infinitesimal quantities... Which is how it gets in your tank to begin with. It's only when you add ammonia- the stuff it eats- that it reproduces to the point of keeping your water healthy for your critters. That's what the "cycling" fish do. They provide ammonia.

And no matter what you do, that's going to take 3-4 weeks to get up to speed- and you need to be diligent about testing for ammonia, nitrite and nitrate through the entire process.

Welcome to the wonderful world of cephalopods. Keep asking questions- your enthusiasm is contagious!

Rock on, Jimbo

PS: Yeah, I kept seahorses (H. abdominalis) with several different octopuses successfully, but you should heed the advice given to you in this forum- for your first go at ceph husbandry, stick with an octopus-only tank.
Just my :twocents: of encouragement here...I agree with everybody above. Hang in there, and don't get discouraged. The LFS guy really does seem to be clueless about cephs...I don't know the guy, so I suppose I shouldn't be too critical, but... Perhaps you should point him out to Tonmo.com!

Hi Rockthis,

You've been given some good advice by Colin and our other members.

My advice is to slow down and let your tank cycle naturally. As Colin mentioned, it would be good if you waited a couple of weeks before adding the fish. Maybe the LFS could keep them for you.

Experts used to say your tank shoud be set up and mature for 6 months before adding an octo, then later it was down to three months. I actually waited 4 months before getting Ollie because I encountered a slight problem.

The cleaner shrimp, which I bought thinking I'd leave in the tank for the octopus, proved to have a winning personality. So, I had to set up a second tank, this one a 19-gallon invertebrate tank, which is lots of fun. Meanwhile, my big tank develped lots of amphipods and other life. Ollie lived on amphipods and other creatures from the live rock the first few days he lived with me, and later he still continued to hunt for amphipods.

Be sure to have a look at my Checklist - it's for people thinking about owning an octopus.
Cephalopod Care

All the best,
Thanks everyone, i returned my tank and i am getting a 50gallon one (didnt end up costing me near 1000 :biggrin2: ) I have read all of your replies dilegently and i plan to take my time with setting up the tank, but i still have one more question.

I still have live rock ffrom my first tank should i keep it?

thanks a bunch
P.S when i get my tank and i am ready to start cycling it will u guys help me through it? :mrgreen:
Live rock is live rock, no matter who you buy it from, so I would say to keep it...of course, it depends on where it is originally from. Right now, all of the rock seems to be coming out of fiji...brown with red speckles. Not too bad...
I would just use it. I am also happy to hear that you are plugging away at the myriad problems you have encountered...Way to go!!!!
Rockthis11, you got another first name? LOL :biggrin2:

Anyway, glad to know that you are studying up on stuff, why not visit a local library and they are bound to have books on setting up a saltwater tank... an octopus tank really is just a specialist invert tank

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