Hi folks. So I've been researching and planning (Buggin my eyes out reading) for the last month on starting a 15 g reef. Then I run across this board with the words coldwater tank. I'm hoping the story begins here.

I live in almost the center of the North American continent in Winnipeg, MB, Canada. Currently the outside temperature is -25 celcius (-23 F). I don't like paying bills (I'd rather spend it on fun stuff), so I keep parts of my house 13-19 degrees C (50-66 F). My house is well insulated, so in the summer when it's hot out, parts of my house will still keep at that temperature (basement and shady parts of the house.). Hmm. Sounds like cold air/water/air/water cold water tank. I keep 2 freshwater goldfish tanks without heaters. The fish are happy (as far as I can understand happiness to a fish.?)

Here's what I would love to be able to do. Set up a 15g coldwater tank. I would like to experiment with growing kelp (Maybe even for consumption once in a while. And I know higher light for kelp will give me algae, but I don't mind scrubbin.) , seagrass, some nems, inverts, all coldwater variety. NO FISH. I know. I live in the center of the continent, and it's going to be hard for me to get any CW stock, but we'll cross that land mass when we come to it. First . . .

Now I've been trying to leaf through all the CW tank threads, and resources, but I still don't seem to quite understand filtration, cycling, of a small nano coldwater tank. The larger tanks seem to not use any live substrate. Straight Aragonite sand? Where does the cycle start? Does the the filtration happen in in mechanical filters? Cycling could take 5 months I read somewhere? Same kind of salt mix as tropical reef? Questions questions.

I've currently collected a tank, an ac 110, some base rock. Just not sure how to begin a CW project. Any advice would be greatly appreciated. Or a link to a more compiled step by step nano CW setup would be great. Thanks in advance.

-Simon.

Jaimie or Jacob could answer better than me most of your questions, but from what I understand you could cycle at a warmer temp, say 65 - 70f and then slowly drop that to 50-55f after the cycle ( warmer temps lead to higher metabolic rates, meaning faster cycle). Secondly it seems that a chiller is standard operating procedure, i've looked into ways of avoiding that expense but its not feasible (could do DIY if your handy ). A coldwater tank can cost you as much if not more than a tropical tank, and the hobby is expensive as is. I'd recommend taking the time and money to do it right, rather than losing money and livestock due to cuting corners.

Filtration, in the simplest terms, is just like filtration for a reef. Bacterial colonies on whatever substrate you have along with water changes provide the majority of your filtration. Adding a skimmer and an often cleaned canister filter would be good advise as well.

Cycling in coldwater tanks can be done a lot of ways, depending on the situation. The quickest, and least feasible, for you would be to collect rocks from the ocean from water of the appropriate temperature and drop them in the tank. Assuming you can't just go and do that, the next options are to cycle it at tropical temperatures, then slowly drop the temperature over time. IMO, 2* of dropdown temperature per week is about as fast as you'd really want to lower the tank temps. That means about 4 months from tank start to adding any livestock. The other option is to cycle at lower temperature. Expect that to take 6 months - that's about the time you'll see huge diatom blooms. You can do this by getting the tank running and adding some fish food every few days to jump start the nitrogen cycle or you can do the trusty and outdated "damsel method" where you drop in some coldwater livestock to start the cycle.

Most coldwater tanks you see don't use aragonite sand, but substrate is an aesthetics issue. We mostly choose large, round cobbles because most of the shorelines that the livestock is collected from is made of larger rounded rocks instead of sand. Similarly, you don't see limestone reefs in coldwater environments like you do in tropical reefs. Coldwater reefs are made of a mixture of anemones, hydroids, and sponges more so than stony corals. But again, thats all up to you. From a filtration standpoint, sand and tropical live rock is superior to large cobbles. From an aesthetics standpoint, rounded cobbles looks more realistic.

With the exception of salinity and a few parameters we hobbyists don't care much about, ocean water chemistry doesn't vary much across the globe. Any tropical salt mix will be fine.

The basics of coldwater reefs aren't much different than tropical reefs, with a few sticking points. The filtration system is slower because of the temperature, and yet we need to get rid of more nutrients because nearly all of the livestock is nonphotosynthetic and require large daily feedings. If you're going to spend money, do so on filtration. Subdued lighting is better to reduce algae growth and keep the livestock open. For this reason, I would highly recommend against trying to grow kelp in the tank, at least until you've gotten a handle on the "basics" of the husbandry.

If you want to follow along with a current build, dtfleming just made a thread last week about starting up a coldwater pico, or take a look at the coldwater tanks listed in the stickied threads at the top of this forum. Many of those will have initial setup information.

Good luck finding livestock.



I have to disagree with Markushka on one point - my coldwater tank is the cheapest marine tank I've ever made (except for the pest anemone tank)...that includes several 5.5g aquariums. The livestock is cheap, provided you aren't buying the crazy expensive boxfish on Live Aquaria. The price of lighting is offset by the price of a chiller - but you don't have to buy new lights every 6 months or year, and many people don't even require a chiller due to their normal house temperatures. If you don't need the chiller, it's basically a freshwater tank that requires some salt and a skimmer, if you're lazy about water changes.

Thanks for the info! I just found temperatereef.com. Starting to understand a little more.

Question about the substrate and rock ( Since I have no access to the ocean, and already have some sand and base rock) . . .

Is there a problem with using arag sand and calcite base rock or does it collect too much junk from the feedings of the nems?

Is there any need to use tropical live rock to kick start it or would that just be a waste of $$ since the tropical stuff would probably die off anyways?

Am I understanding incorrectly that I can cycle a CW tank just like a tropical with the same substrate and rock, then simply lower the temp slowly and I'll be set to add temperate species?

This would great since I'm not in hurry, so I can cycle for a couple months, then when it comes time, I can try to locate CW stock, if I'm really outta luck, I can just continue with tropical s.

Thanks again for the info! Off to get some salt mix.

Is there a problem with using arag sand and calcite base rock or does it collect too much junk from the feedings of the nems?

--no, there's really no problem. the big stuff collects as much, maybe more, detritus with all the large pore spaces that don't get much water flow.

Is there any need to use tropical live rock to kick start it or would that just be a waste of $$ since the tropical stuff would probably die off anyways?

--need? no. if you drop the temperature slowly, some things will survive - some pods and feather dusters would probably be fine - but the majority of the tropical stuff will die off once you get below about 68-70*. it certainly can't hurt from a cycling perspective.

Am I understanding incorrectly that I can cycle a CW tank just like a tropical with the same substrate and rock, then simply lower the temp slowly and I'll be set to add temperate species?

--thats essentially how mine got started. i found an anemone species that could survive tropical and coldwater at a wholesaler in 80* water. put it and the rock it was on in a 10g with a bunch of pebbles and dropped the temp to 58* over 6 months. as with tropical tanks, when you add temperate livestock, go slowly. patience is required in tropical, but to a much greater extent in coldwater. every time you add livestock, you change the nitrogen cycle in the aquarium. in a tropical tank, it's a week of adjusting. in a temperate tank, it's a few months.

This would great since I'm not in hurry, so I can cycle for a couple months, then when it comes time, I can try to locate CW stock, if I'm really outta luck, I can just continue with tropical s.

--the national zoo uses a vendor in vancouver, i believe, for their aquarium livestock - including temperate species. i don't know if they sell to the public, but you might search around for them.

I admire the chutzpah you show by taking on this challenge from the geographic center of the continent. Go for it! It's fun to help guys like you do audacious things like this.


Filtration:
Biological filtration works by providing a place for sufficient numbers of aerobic (oxygen loving) bacteria to live. The bacteria "eat" the ammonia and nitrites produced by your livestock, and convert it ultimately to nitrate. You then need to get rid of the nitrate either by doing lots of water changes and/or by also providing a place for anaerobic (oxygen hating) bacteria to live. Anaerobic bacteria convert nitrate to nitrogen gas, so fewer water changes are required if your tank can support anaerobic bacteria too. Tropical liverock is very porous (because it is limestone), and so provides LOTS of surface area for BOTH types of bacteria to live. That is why it works so well as a bio-filter. If you put it in your coldwater tank, it will work just as well as in a tropical tank, just more slowly. You want the porousness, but you don't want all the tropical animals living on the rock at your LFS because 95% of them will die in cold water and pollute your tank. I think you want to buy dead "liverock" at your LFS, and then cycle your tank (feeding it fish food or ammonia daily) at tropical temps until you have a nice population of bacteria keeping your water clean. Then crank down the temp slowly (while continuing to feed the tank), hoping that the bacteria will adapt to the temp drop (evolve), and not just all die. The assumption here is that the species of bacteria that will grow quickly during the warm water cycle will survive at a cold temp. If that assumption is wrong, and different species of bacteria live at different temps, then the warm water cycle will be a waste of time. I would be inclided to drop the temp faster than two degrees per week (3.5 degrees per week? (1 degree every 2 days)) but that's not based on science, just impatience.


"Regular" rocks, like river rocks, are not limestone, and are, by comparison, not porous and provide only a tiny fraction of the surface area provided by tropical liverock, and so can support only a tiny fraction of the bacteria. I don't know how some of the coldwater tanks I see here function with only this non-porous rock and no real filtration system. Maybe they keep very few animals and don't feed much, or maybe they do LOTS of frequent water changes (or maybe I'm just missing something!). IMO you should either go with dead "liverock" from your LFS, or get an external filtration system (I use a wet/dry filter and RDSB on my 60 gallon octopus tank - no live rock (doesn't look natural to me in a So Cal biotope))

You will be feeding a lot because most coldwater animals don't use light, so if you want reef quality water, you'll need more liverock than a tropical reef tank.

Chiller:
You may have a room in your house that is 60 degrees, even in summer, but remember, if you want your tank to be 60 degrees, the room might need to be 55 degrees, or so, to compensate for the heat added by your pumps and lights. Will you spend much time admiring your tank if you have to do it in a room that cold? If not, you might need a chiller.

Cost:
My tank has been cheap to set up, and to operate compared to a tropical tank, but I think that is mostly because I collect my own livestock and feed my octopus frozen shrimp and scallops from Costco. If I had to buy livestock at LFS prices, and watch lots of it die as I learn a few things the hard way, the cost might hurt. On the upside, coldwater animals, especially tidepool animals, are tough as nails, so you may not have much die off, especially if you do your homework before you buy.

Kelp:
I think I've read that kelp is tough to keep alive. The only person I've hear of having success growing kelp in a home aquarium is a guy in Norway (Link to his very interesting tank blog)

He had a very large tank, and simulated strong alternating surge.

Couple of things, c-rad.

you should read the article Fosi wrote on the nitrogen cycle (specifically on anaerobic bacteria).

having standard live rock isn't a bad choice - especially cheaper base rock. some of the life on it may survive the temperature drop. what doesn't will pollute the tank, but that is really no different than tossing in a piece of table shrimp or some fish food to "encourage" the cycling process.

adaptation =/= evolution.

moving faster gives less time for adaptation. in a niche where the normal cycling process takes 6 months, you should certainly understand the need for patience. this slow drop also negates any worry about the change of bacterial species as the temperature changes, because the die off of one species is slower and allowing more time for the next species to take over. increasing the speed of dropping the temperature is likely to only cause a longer cycle due to the inability of the system to stabilize before the next big drop.

coldwater livestock is cheaper than tropical. compare the price of the "beadlet" anemones on live aquaria to just about any coral and you'll understand that quickly. look at the prices on the aquarium setups from gulf of maine - an entire 10g worth of livestock for $275. price really isn't the concern in the coldwater hobby - it's simply a matter of finding a vendor.

you should also read steve weast's take on keeping kelp. based on his comments, the only "difficult" part of keeping kelp was getting rid of the excess nuisance algaes - in itself a task not suited for beginners, but by no means is keeping kelp a difficult thing.

Awesome, thanks folks! So basically, I can start a slow cycle either by dumping in some of my dirt cheap goldfish food in a tank of cheap base rock , or buying a small piece of $10/lb live rock and dumping that in a tank of base rock. Hmm, doesn't seem like a hard decision to make if I have the time to wait.

What kind of media do you folks run in a filter of a CW setup? I have an AC110 that I was going to mod to a refugium. Can cheato adapt to a low temp?

I was thinking cheato might survive at low temps too, I haven't tried it yet, but since cheato grows so fast anyway it might be worth a try. Also, CW macro algaes are another option, I like mine, they are relatively fast growing, and absorb nutrients.

I use a fair amount of cured live rock in my 5.5. If you
view pics of my tank you can see the tropical rock
that the metridium anenomes have made a home on.
I also have live rock rubble in my AC 30 filter along with
carbon. The majority of the of the rock are fragments
of shale and boulders. If you are able to collect your
own live coldwater rocks, you get the benefit of inheriting
cool hitchikers and bacteria. I use a somewhat course
river bed sand that is almost the same as the sand
you see at the tidepools. I purchased the sand at my
LFS, and it resembles mostly tiny pebbles. Purchased
livestock is a challenge. There just are not many dealers
that sell coldwater livestock to the public. Occassionally a
Beadlet anenome will show up on Liveaquaria or Catalina goby,
so you just have to keep your eye out for that stuff. I
sometimes go to the asian seafood market to browse and
inspect oysters for chitons and mussles, that is where I
found my mossy chiton.

Welcome aboard, H

not sure about chaeto, but california has a ban on caulerpa for a reason you could certainly try it. for a filter, i'd add a couple of sponges and change one a week, alternating which one you remove.

horus...great idea (why haven't i thought of this?). looks like i'll be heading into chinatown soon

For "filter media" I use 6 gallons of bio-balls in a wet/dry filter, for a 60 gallon tank with a heavy bioload (octopus, heavy feeding). The wet/dry has a floss pre-filter on it, which I change every two or three days. I have a 4-5 inch Deep Sand Bed (but I really should add a RDSB (Remote Deep Sand Bed) to better reduce nitrates) I do 20% water changes every 10 days or so. My rocks are all local ocean rocks and don't provide any filtration.

The plants in a refugium will capture nitrates, and so reduce the need for water changes, but you need something (liverock, wet/dry, HOB filter, ...) to do the bio-filtration (ammonia => nitrite => nitrate)

BTW:
What do you all mean by "base rock"? is that just regular non-porous inland "rock", or is it porous limestone, like live rock, only without much living on it? If it's not porous, isn't it true that it will only provide a small amount of bio-filtration?

Sure. My point was that non-porous rock won't do much filtration (so avoid regular rocks), and save money by getting the cheapest porous rock you can find.


I know, I was unclear. What I meant was that the bacteria weren't only adapting, they were also evolving (the most cold tolerant individuals were being selected in each generation). I don't know which process is happening more, but it seems reasonable that both are happening.


My recommendation (1 degree every other day) will take a month to drop from 75 degrees to 60 degrees. You suggest 4 months (right?); aren't we each just guessing? We know that if you start with almost no bacteria, it takes six months, at 65 degrees for the population of bacteria to increase enough to do the job. So we know they reproduce slowly, but does that mean that they "adapt" to temperature change slowly? The two are unrelated, we're guessing about how fast is too fast to drop the temp. If however they are doing more evolving, and less adapting, then the slow reproduction DOES mean that we need to drop the temp slowly, but even then, the best rate to drop the temp is proportional to the reproduction time (which is measured in minutes to hours for most species of bacteria) How many generations should we wait before dropping the temp one degree? What percentage of the population will die for each 1 degree of change? It's all guesswork, unil someone does some experiments. Maybe you've seen some experimental results I haven't, but I don't see a reason yet to prefer your guess over mine, and I did include the disclaimer that my 1 month recommendation was "not based on science."


Interesting points. Is it true that different species dominate in different temp ranges, or do the population densities of each species remain about the same over the entire temp range? They all get slower as the temp decreases, but do any of them die? If I know that I can leave a chicken breast out at room temp for four hours before it goes bad, what happens if I put it back in the refrigerator after two hours? The bacteria stop reproducing (mostly) but they don't die - the meat doesn't get sterilized. If I take it out of the fridge again the next day, the bacteria will pick up where they left off. I'll only have two hours before my chicken goes bad, not four. Based on this, I think it is reasonable to suspect that maybe I can lower the temp in my tank from 75 degrees to 60 degrees in an hour, without doing any damage to my bacteria population. I see a reasonable argument to support cycling, with no livestock, at 86 degrees (see below), and then dropping the temp to 60 all at once. In spite of this, I still recommended taking a whole month, just to be prudent. I am one patient guy.

Base rock is common usage for chunkier pieces of reef limestone that don't have the nice coralline algae and pretty shapes at substantially cheaper prices.

While I agree that nonporous rocks aren't as good for bacterial colonization as porous rocks, it by no means negates their use in the aquarium. If you take a look through the coldwater tank threads on NR, you'll find that the majority of us use those nonporous substrates due to the aesthetics - filtration can come through many other sources than simply the substrate.

Again, adaptation =/= evolution. Natural selection (what you are describing) is indeed a step required by evolution. But natural selection alone is not evolution. It is adaptation.

My suggestion (72* to 60*) is a mere 6 weeks. Add in a month for cycling time, and we're talking just over 2 months.

We do, in fact, know that the bacterial population responds to temperature change. This is well-documented - do a simple Google Scholar search and you can find many papers that discuss this. There are also studies that suggest that temperature changes result in a quasi-hibernation (my own term, but fairly accurate) in which the marine bacterial population decreases productivity rapidly with lowered temperatures (especially in temperate environs) and may take weeks or even months for productivity to rebound (see Pomeroy and Wiebe, 2001 as one example). It would seem that the slower the temperature is dropped, the less likely this hibernation would occur. Yes, my suggestion is still a guess, as we have no reasonable way to test this process. Based on the research and my experience with my tank, and helping others set up their own temperate aquariums, I have concluded that slower is better. 2*/week seems to be a good compromise between moving too quickly for tank stability and testing a person's patience too much. Were it reasonable, I would suggest that people go more slowly...but I already see enough silly arguments over my current suggestion.

We also know that bacterial populations vary spatially across the globe (see Lee and Fuhrman, 1991 as an example of a study in which 3 ocean reservoirs were analyzed and found less than 16% genetic similarity amongst the sites). Many variables come into play here, but it suggests that the bacterial population is not the same from the initial cycling period at high temperature to the final cooler temperature in the aquarium - even if all the species can survive, different species will dominate based on their preferred temperature regime. If that is the case, then we again have to spend time waiting for those populations to equilibrate.

Well, it looks like we're getting a good debate on going on the argumentative theoretical praxis of evolutionary adaptation of an adapted evolved sapian erectus species. Sounds good to me folks.



I plan on setting up the fuge with compartments, one for sponges/poly/carbon, one for sand+rubble, one for macro's (Ones that I'll see if they adapt to CW)



The base rock that I've got for cheap is calcite based porous rock. Same stuff used in tropical reef, but cheap because it's dry and dead.

This sort of brings up a question. Are the bacteria that do the biological filtration in a tropical reef, different than the bacteria in a coldwater reef? If so, we shouldn't we be starting with coldwater "live rock". Which I'm gathering doesn't exist on the market, just at your local ocean next door. Hmm.

-Simon

*sigh* Don't mind the adaptation/evolution argument. Scientists tend to have a difficult time letting go of misused terminology



Based on the 1991 paper I mentioned, yes - the workhorse bacteria are different species in different temperature environments. So the obvious answer to that next question is yes, it would certainly be preferable to have coldwater live rock...only available from the ocean or your friend with a coldwater tank.

The assumption, however, is that some of the species suited to coldwater life will either "magically appear" in your tank at some point in the process of cycling or (more likely) are present in some small number on the tropical rock and then will take over as the temperature changes to better favor them.

I'm willing to let actual research break up my wild speculation party. Thanks dshnarw for pointing us at some research.

Assuming that this research is applicable to a tank environment where the only thing changing is temperature, it suggests that there's no advantage to cycling the tank warm and, then lowering the temp, regardless of the rate of decrease. If the species of bacteria that will be dominant at 60 degrees won't proliferate at 72, then we are wasting our time, and would be better off just starting at 60 degrees. I know that's a simplistic argument since the proliferation of any given species is a bell curve with respect to temperature, not an all or nothing thing, but still, the point is valid. More accurately, what I'm taking from this discussion is that we should start cycling at the warm end of the temp range within which the species that will be dominant at our target temp can thrive. Then we should "slowly" decrease temp to our target temp. True, but useless, until someone determines, experimentally, what the right temperature range is. At times like this it would be nice to have a team of eager grad student minions willing to work for peanuts doing these experiments for six months. Oh well, I can still speculate wildly...
If I don't have to pay a subscription fee, I'll read the paper you pointed out. Maybe they can help me draw the bell curve around 60 degrees.