View Full Version : Live rock/Sand with low temps???

06/27/2012, 08:50 PM
Whats up guys, I am an experienced saltwater hobbyist and I am once again considering an octo. I had built a tank years ago specifically for a bimac from octopets, but that business shut down, so I ended up just using it as a reef tank. I'm considering converting my 125 over to saltwater for an octo from LiveAquaria since it seems to be the only place that has them regularly. One thing I haven't been able to find clear info on is the LR and Sand in these lower temp ranges. Do you guys just use typical stuff from fish stores with no issues? Ive seen some LR places online giving recommended temps. Does the beneficial bacteria need to stay in tropical temps, with average store bought live rock, or can it go down into the 60's with no issues? Also, I know the species from Live Aquaria can be hit or miss, but do they have one species thats more commonly sent out than others? Just trying to gauge what i'll most likely end up with if i do go with them. Thanks in advance.

07/01/2012, 10:42 AM
Come on guys, nobody??? Just want to know if you guys use standard LR/LS in your ceph tanks. And if their are any differences to cycling it in colder water?

07/01/2012, 11:48 AM
I've never kept a cold tank but you shouldn't have a problem bringing standard live rock to colder temps, but I'm not sure how sponges or anything on the rock (if you have anything like that) would do.

07/02/2012, 10:33 AM
I'm mainly just concerned about the beneficial bacteria of the LR. Looks to me like most people are using regular LR from the pics I've seen. Just want to make sure I have all the details worked out before I even start gathering stuff for the build.

08/22/2012, 05:18 PM
Sorry i might be late but I'll throw in
my two cents worth. Bb is not as effective as in tropical tanks. And it takes alot longer to get up to speed. But I have kept mine in the 60-70 range and had it established after a month or two. And I was using lots of Special blend bacteria. In one tank I used an established sand bed. Sand seems to work. I have also used pea gravel with success. The main idea is to use as much mechanical filtration as possible so it takes the bio load off everthing. The simple way to put it is don't rely on bio filtration. It's just one tool.

10/19/2012, 08:16 PM
The bacteria won't die unless youre letting your tank get in the 50's however they will slow down considerably.

10/30/2012, 04:45 PM
I've kept wild caught bimac octopus for about four years, at about 60 degrees. I decided not to use live rock because I thought it would look wrong to have tropical live rock in a biotope tank with only local So Cal animals. I also wanted to reduce the chances of exposing my bimac to any non-native parasites or pathogens (and also because I'm to cheap to pay for live rock). I use 9.5 gallons of bio-balls in a wet/dry trickle filter, and a deep sand bed in a 60 gallon tank. I get slow nitrate buildup when I keep just an octopus and feed sparingly (the DSB can handle it) and fast nitrate build up when the tank is full of other animals (sea stars, gorgonians, strawberry anemone) and I feed heavily. It took about six months (at 65 degrees) before the DSB (anaerobic) was able to keep the nitrates down, but the aerobic bacteria in the bio balls was ready after about three months. Then I dropped the temp down to 60 (55 for about 6 months).

The bio-filtration is much slower in cold water, but so is the metabolism of the animals, so you can feed less often to partially compensate.

One advantage of the trickle filter is that it really oxygenates the water well, which is good for an octopus, since they are sensitive to low oxygen, and since I covered the tank completely to insulate, and to prevent escape. Good mechanical filtration is a must with bio-balls, and a good idea with a cold tank in general, because most cold animals can't use light to make food, and so must be fed a lot, and you want to get the uneaten food out of the water fast.

FWIW. I found that the 6 to 1 ratio of water to bio-balls works great (less may also work great), and the in-tank DSB does reduce nitrates, but not enough to keep up with the heavy feeding of a fully stocked tank. For my next cold tank build, I'll still use bio balls, filter floss, and a skimmer, but I'll add:
1) An alcohol-fed nitrate filter (home built, with an automatic dosing pump)
2) A CO2 scrubber (easy home build) to reduce the CO2 lever of the air going to the skimmer and keep my PH from falling (a problem in cold tanks)
3) And a poly-pad (to remove copper, and other contaminants chemically)

With that set up I will be able to load it up with animals and feed it an appalling amount every day.

It's not too hard to catch your own bimac if you know where, when, and how to look, and can get to the beach in So Cal (and yes, it's legal with a fishing license to catch octopus). PM me if you want to know more about the when where and how.