[Octopus]: Ripley - Abdopus sp My 'cephalopodic' journey-a beginner's progressive notes


Feb 22, 2017
Being new to the saltwater side of the hobby I thought it would be great to post as I make way along to not only learning about keeping a marine tank but the steps as I work my way to finally owning my own cephalopod in the future. This will helpfully also be able for me to get tips from everyone as I post my progress so I can learn as I go. :smile: So please-feel free to give me any tips or advice as I always appreciate it.

I started out with what I would recommend anyone doing is lots of researching, reading, chatting with fish stores. This allowed me to see if this next step was something I was ready for as well as would be willing to take on the challenges that come with it, and I will say that there have been a few for me already.

I was fortunate to find a somewhat local fish store that specializes in salt and marine tank.
I am going with a smaller sized tank though it is not recommend to go anything less then 30 gal as it can more difficult to maintain. Fortunate for me biocube tanks have come out with some nice tanks. I went with one of theirs.

For beginners like myself I did find this book to be helpful in learning about keeping saltwater tanks in general:

I am going with a smaller tank with the hopes of down the road getting a smaller dwarf sized octopus or cuttlefish.

The first big difficulty I ran into so far has been getting my tank drilled. The point of drilling it was to attach my display tank to a sump and a skimmer. The majority of glass retailers out there are not all that willing to cut them for you. The one I ended up going through ended up cracking my tank and making a real mess of things. A bit frustrating. On top of this-my live rock and sand was starting to dry out due to how long it was taking to get the mess figured out. So it was back to the drawing board you could say-I again am lucky to have such a great local fish store who not only helped me purchase a second tank they then drilled it for me.

The next step was setting up the tank. Due to being new to this I did pay to have help here. Which I will say I am glad for as after seeing how to do it-which I probably could do it now on my own, I doubt I'd have been able to figure it out so smoothly without someone showing me.

Naturally with any first tank set up it will look quite dirty in the water until it has a chance to settle down.

Once settled it was looking rather spiffy. :smile: I am using the biocube stand with it.
I will point out that there are not very many rocks in the tank-for an ceph they will need a lot more then what I have. But I am working up from a beginner so will be trying my hand at a few hardy critters first then some coral and work up to a ceph!

Another small challenge to note: I had a power strip I used that had timers on it but was very difficult to figure out when it was on versus off. Well-I thought I had it set right until water started pouring out from the sump. After a moment of panic- I figured it was because one of the power ports was set to its night setting turning it off while allowing the other pumps to continue. So lets just say I dumped that power strip out the door. Pretty tired of messing around with that thing.
Currently my local fish tank owners and I are working on getting a stand for the skimmer as it is sitting a little to low then we would like. We also will be changing the piping on the side that is currently cycling the water due to it makes opening the full hood difficult.

But it has the tank up and flowing.
I just tested my water this week-happy to say that it seemed my live rock and sand may be fairing better then I expected. The water tested with very low nitrates and nitrites. The Specific gravity at 1.025 but the PH is a bit high at 7.8.
I am planning to let it run another week and then see about possibly adding a single small fish. For those who are already experienced and ready for a cephalopod tank-I've heard its best not to use fish. But as I am learning from no experience I am planning to try a few hardy fish to get my skills up.

Another side tip I learned from a recommendation from a saltwater book I read is to keep a journal of your tank. This way you can more easily watch its numbers and catch things early before a crash. I plan on starting a journal so I can take notes.
:thumbsup: It is nice to see that you have successfully started up the tank. Initial low ammonia/nitrite readings can be misleading. Your "live rock" may not contain much bacteria (since you mentioned it getting dry and the white look implies dead, not live rock) so be aware that if you don't go through a high ammonia, high nitrite phase, you likely do not have enough bacteria to break down waste and will see a spike in both as you add critters. You may want to add at least one more piece of active rock before adding your initial fish. Additionally, adding a grocery store shrimp and a hand full of hermit crabs to encourage active cycling will help kick start the bacteria growth. Some of the more hardy fish will tolerate spikes but making sure you have a good bacteria base will result in less loss, cost and heartache.

Your PH is LOW (more acid than it should be), not high (more alkaline) at 7.8. Your target should be about 8.3. Are you mixing your own or buying premixed water. If mixing your own are you using RO/DI, distilled water or tap?
Thanks and thanks for helping me figure things- okay; I'm using premixed salt water although I was also informed to add RO water (as my tap water is well water) as the water levels go down.
I have also noted a sudden splurge on a reddish brown algae on both the rock and sand. Is this good/bad?
I also have live rock in the sump below that is not seen in the photo. But yes I was wondering on that aspect.
The reddish brown is likely just algae but if it is slimy/stringy and sort of purple it could be cyanobacteria (thought to be the beginnings of life by some scientists - likely because it is hard to kill :biggrin2:). Cyno is not particularly dangerous but is hard to eliminate (extra and large water changes and siphoning). Brown algae is not a problem but is unsightly and is removed through scrubbing, siphoning and water changes. After the tank matures and with regular maintenance, you will see less of it.

You should start the habit of doing small water changes and cleaning the tank about once a week. At the moment and up until you have a large bioload you can easily get away with doing this every other or even once a month (change the same amount of water but in smaller or larger quantities depending on your schedule). However, once you have an octopus, weekly cleaning and water changes are highly recommended.
Yep-algae the aspect that seems to have a factor in the tank hobby.
Weekly cleaning is already a habit of mine- I go through my 50 gal freshwater every week. :smile: So adding the salt tank to my weekend maintenance- no problem!
I've been wondering over this and either haven't ran into an easy answer or found one that I've been able to grasp-on water changes with the marine tank- how do you know when to add more saltwater and when to just add RO water?
Is it based on your hydrometer measurements?
(I know with evaporation that the salt stays in the tank)
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When you do water changes, you will always exchange saltwater for saltwater. You will top off the tank, ie replace evaporated water with fresh (RO/DI or distilled). Salt does not evaporate so your tank will become extra salty if you do not top off regularly.

However, you should check your salt levels roughly once a month when the display and sump are full while you are learning to care for this specific tank. Even though you will not lose salt through evaporation, you can lose it to "salt creep". This happens when water splashes and evaporates in places where the salt will not return to the tank (hence the reason for testing when everything is full). The loss is small but can accumulate over time (or with active splashing). If the salt will reenter the tank (ie it has dried on the sump walls) when you add water, do not try to compensate for it. If you determine the salt level is low, first check your new saltwater for correct salinity (more often the problem when salt creep is minimal). To compensate for salt creep, top off with saltwater until the correct salinity is achieved, ie don't try to compensate all at once - "nothing good happens quickly in a saltwater aquarium".

Compensating for low salt content in your premix will (after complaining to your LFS) requires the purchase of a small box/bag of Aquarium salt (I recommend keeping some on hand for emergencies since you will be keeping RO water that can be used to mix with it should you need saltwater when you cannot get it) and experimenting with adding it to your premix. This should not be necessary and is likely a one off condition. For those of us who mix our own at home, monitoring our mix is more important.
Okay- great advice and thank you for explaining the water change more easily to understand.
I took your advice and purchased some aquarium salt to have on hand in case of an emergency
I retested the water and its pH actually was higher. (The previous was tested through a dipstick approach which isn't always reliable)
As it has been a week, I did a 10 percent water change for it, was able to get my skimmer working and running as well.
I know you recommended hermit crabs as a starter but I was not able to obtain any. Instead the next option I was recommended was blue chromis fish. Hopefully that is also an agreeable go to.
So far they seem good and healthy. I'm keeping an extra close eye on everything.
But yes, I always try to avoid any heartache to any loss of animal life.
Fish will work for cycling the tank and Chromis are both hardy and attractive. However, they are very hard to catch and should not be left in the tank with an octopus. There are multiple reasons for avoiding fish in an octopus tank. My primary concern is for the octopus. Fish, especially hardy varieties usually try to hang out with the octo and pester it, resulting in a shy animal. Eventually the octopus will kill it and there is the possibility of the fish nipping the octo and opening it to infection. You will likely be able to trade it back in for some kind of credit before you add your desired animal (if you can catch it) but be aware that you will likely disrupt your aquascaping.

The reason for suggesting hermits and later serpent stars (a favorite and these will often learn to be hand fed) was because they could remain in the tank as clean up crew and be over fed now to help grow the cycling bacteria. You can still add them as time goes by.
Okay great- yeah I was figuring that. So I have not done any aquascaping yet just for this reason. The store already were planning on using them as testers and then trading them back. They suggested then due to how inexpensive they are in case something went wrong.
This is great to know on the hermit crab and Starfish. :biggrin2:. Will they still be able to be added even though it's a 30 gal with a sump? Im not as familiar with saltwater fish spacing. I don't want to crowd. Also I believe you pointed me to a few starfish below- but is there one you would think would be best suited for my tank set up?
One serpent star (not starfish, similar but different behaviors) and pretty much all the hermits you want to add will be fine in a 30. The hermits may or may not become snacks but the serpent star will outlive many octos. Both are meat eaters so they will need to be fed some form of ground up meaty food. The hermits will do fine on fish food but I have only fed my serpents ground shrimp.
Sure snails are helpful. I have found that it is best to choose either snails (more than one) or hermits but not both as the hermits tend to kill the snails for their shells. Hermits tend to get into the LR and sand where snails are better for surfaces, including your glass. You CAN have both but may have to experiment with the type of hermit (there are quite a variety).
Tested my water again this week and the levels read again at the low to hardly any nitrate or nitrites. I've now had two of the temporary fish (as once I get my octo there will not be any fish with him) to help prepare the tank, one small green mushroom coral, and I just this week added 2 snails. The snails are to start helping with the sand and glass.
I do plan to still purchase hermit crabs as in the long run the help with cleaning the LR and Sand is what I need.
I was suggested that the type of snail I purchased tended to get along better with hermit crabs due to their shell shape. Maybe. Hope so but will have to see like your warning states. If I have to chose one over the other I'll end up sticking with hermits. I am also looking into different hermit crabs to see what I can find.


Here's the two snails I currently added for clean up crew starters.

Also in regards to hermit crabs:
This is one of the hermit crab types I am looking into:
Saltwater Aquarium Crabs for Marine Aquariums: Halloween Hermit Crab
Trying to find one that is colorful and peaceful.

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