Re:nano tank suitable?

Dear Ella:

The 24-gallon nano tanks are indeed compact and convenient, but they have some serious drawbacks for seahorse keepers. A number of our other members have tried fairly large (24-gallon) Nano cubes for seahorses and found them to be unsatisfactory.

Other Club members who have tried the 24-gallon Nanocube for their seahorses report that it is quite unsuitable right off the shelf and requires substantial modifications in order to make it marginally useful for seahorses. For starters, they have a bad tendency to overheat, the pump needs to be upgraded, it has no means of filtration so you must provide a biofilter of some sort, and small powerheads should be added to eliminate dead spots and improve the circulation. Even with those modifications, you must stock the Nanocube sparingly, be very careful to avoid overfeeding, and practiced an accelerated maintenance schedule, including weekly water changes.

As an example of what I’m talking about, here’s an exchange from the discussion forum regarding the 24 gallon Nanocube:

Hey everyone! I’ve read the posts about the experiences some people
have had with seahorses in nano cubes and I have a few questions for
them if they catch this post. I have purchased a 24 gallon nano cube
and have done alot of research on it and found out that you have to do
a ton of upgrades on it to make it suitable. The pump has to be
upgraded, there is no true filtration, you should add another power
head for water flow to elimate dead spots. Even then there isnt a
protein skimmer that you can purchase for the nano. So my questions
are where there any upgrades made to the tank? Were you able to keep
other fish alive in the setup or did you give up on it all together?
Thanks,
Nikki

Dear Nikki,

I don’t think that you should have a lot of problems and this is
why. Yes, all of my seahorses have died in a 24 gallon nano cube
setup and I have figured out why. I had a setup with sand, coral,
and two clown fish. I also had the normal cleanup crew snals,
shrimp, etc. I could not figure out why my seahorses kept dieing.

You must understand, that there should not be any other tank
inhabitants within the nano cube when you have seahorses. I would
not even advise sand. All you need is a few hitching post and
maybe, a few large pieces of liverock aligning the back of the
tank. You could add a few snails and only a few hermit crabs.
Note, the hermit crabs will clean up whatever the seahorses will not
eat. You could also add a cleaner shrimp or peppermint shrimp. You
may want to keep it a very low minimal when deciding about adding
anything else in the tank. You don’t want the seahorses deprived of
any mysis shrimp when they are feeding. You don’t want to add any
coral. Why? Because you want to eliminate any possibility of over
feeding and polluting the water. You will also want to do a water
change every week. 20% percent only, and afterwards check the Ph to
make sure it is stable.

I have 2 nano cubes. One nano I have houses
coral, two clown’s, two gobies, crabs etc. No seahorses. The other
nano is a new setup. It is about 2 1/2 weeks old. I am going to
wait about another two weeks to begin adding seahorse’s. At the
moment there are only liverock in the tank. I am not going to add
sand to this tank at all. The live rock are positioned at the back
of the tank. I want to try to leave a lot of open space toward the
front of the tank. Today, I will be adding two snails. I will not
be adding anything else but two hermit crabs only to cleanup after
the seahorses have eaten. The crabs will be added only after the
seahorses have been added. In a nano cube setup, the trick is to
not add too many inhabitants and to do a water change at least every
week or two weeks.

What you could do is add a lot of dead coral
liverock if you can find it. If not, try to find a lot of hitching
post that will work well. Sometimes you could even make them
yourself. So, I hope this has helped you and if there is any
information out there that you or anybody else have please forward
it to me because I am still learning things as I go along. [End quote]

And here is Kristie Cowans’ assessment of nano tubes with her seahorses:

JBJ Nano Cubes and seahorses don’t mix…
Don’t do it, not the Nano cube-I just sold a brand new 24 gallon JBJ Nano
cube only weeks out of the box because with the lights on for 8 hours a day
the water boiled up to 86+ degrees!!! So then I drilled the crap out of the
lid and installed a computer fan-it was so loud it was comparable to an air
driven popcorn maker. While I was researching the fan problem I would drop
frozen water bottles into the tank all day long. I know the owner of the
company who makes JBJ and let me just say he is a shrewd business man always
looking at the bottom line. These Nano cubes should come with a warning
label about how hot they make the tank water. If you want some opinions
about other Nano brands maybe on reef central in the Nano cube section
someone may have better advice-but I regret putting my horse’s through that
kind of heat exposure and luckily none of them got ick from the constant
temp. fluxuation as I would put the ice bottles in the water. Kristie Cowans

For these reasons, I think you would be better off sticking with a more conventional aquarium such as a gay 20 or 30-gallon Extra Tall All Glass aquarium, rather than attempting a 24-gallon nano tank, Ella.

If you want to start out with a low budget set up for keeping a single pair of Mustangs, perhaps the most basic aquarium system I could suggest would be to obtain a 20 gallon Extra-High All-Glass Aquarium (20"L x 10"W x 24"H), equip it with a simple, standard, off-the-shelf glass cover and an off-the-shelf strip reflector with a florescent bulb, and then fit it with a full set of undergravel filters that completely cover the bottom of the aquarium, as described below.

The filtration system for the tank could thus be as basic as a set of well-maintained undergravels (preferably the new reerse flow designs) that covers the bottom of the tank completely. I know undergravel filters are considered old-fashioned technology nowadays, but they are inexpensive, utterly reliable and foolproof (no moving parts), easy to install, require no modification whatsoever, and work extremely well for seahorses within their limitations. An inexpensive diaphragm air pump will operate the filter and provide all the aeration you need, or you can upgrade to powerheads for greater efficiency and extra water movement.

For the substrate with your undergravel filters, use a coarse bed of good calcareous aquarium gravel such as dolomite, aragonite, or crushed oyster shell 2-3 inches deep, since the buffering ability of such substrates will help maintain good pH.

It is a good idea to supplement the undergravels with an inexpensive hang-on-back filter or canister to provide better circulation and accommodate chemical filtration media. This is a very simple, inexpensive aquarium that’s extremely easy and economical to set up and operate, yet it can be very successful if used within its limitations. For instance, undergravel filters are notorious nitrate factories and the hobbyist must take measures to compensate for this fact. This simple system relies totally on water changes to control nitrates. There is no live rock or live sand bed to provide denitrification, no algal filter or denitrator in a sump, and no protein skimmer to remove organics before they enter the nitrogen cycle. This limits the carrying capacity of the tank and makes an accelerated maintenance schedule and more frequent water changes an absolute necessity. For this reason, reverse flow undergravels often work best with seahorses; they help prevent detritus from accumulating in the gravel bed.

I recommend weekly water changes of a least 25% for such a system. Use a gravel washer to clean a different portion of the gravel bed (no more than 25%) each week and keep the tank under stocked. If you are diligent about aquarium maintenance, perform water changes religiously, and limit yourself to fewer seahorses that you feed carefully, you will find that a simple system featuring undergravel filters can be very successful. But if you are negligent with regard to maintenance, skimp on water changes, or tend to overcrowd or overfeed your tanks, this system will be very unforgiving.

It’s generally best to start out with the largest tank you can reasonably afford and maintain, the taller the better, in order to provide yourself with a comfortable margin for error if these will be our first seahorses, Ella. The 20-gallon Extra-High All Glass Aquarium we have already discussed is the smallest tank I would consider using for it pair of medium seahorses and perhaps a pair of Amphiprion occelaris clownfish, but if you can afford to spend just a little more than I would suggest the 30 gallon Extra-High All-Glass Aquarium (24"L x 12"W x 24"H), which won’t cost much more but which will provide you with a bigger margin for error. Any local fish store can order one for you and it’s an economical tank with excellent height for seahorses at 24-inches tall. You can then equip it the same as the 20-gallon tank, using a simple, standard, off-the-shelf glass cover and an ordinary off-the-shelf strip reflector with a daylight florescent bulb, and that can form the basis of an inexpensive yet solid seahorse setup for a total price of less than a 24-gallon nano tank.

If you can afford to upgrade the filtration system a notch above undergravels, many seahorse keepers prefer well-cured, "debugged" live rock to provide all or most of the biofiltration for their aquariums. A simple external hang-on-the-back filter or an efficient canister filter instead that is rated for an aquarium of the size you have chosen could then be added on to provide water circulation, surface agitation for good oxygenation, and the means for providing mechanical and chemical filtration.

Best of luck with your ongoing research into the needs and requirements of seahorses, Ella! Let us know if we can be of any further assistance in that regard.

Respectfully,
Pete Giwojna