Coldwater - tidepool system

[Playdope]

I am designing a cold water tidepool system, and I was looking into which lighting to use. The tanks will be used to study certain tidepool specimens, and doing this under different levels of light is a primary concern. We plan to use screens to dim the lighting levels, and with no screens over the tank we would like to be producing full daylight. We have several tanks that will be encorporated into this system (+-15)

Which type of lighting would be best for this system?

Which bulb type (kelvin rating) would be best for this type of system? Actinics? Would someone mind explaining what the diff. bulbs are used for?

Sorry about all of the questions.

Thanks,
Jon

 

[Unarce]

Hey Jon,

I won't pretend I know what's the best for your experiment, since I don't have a biology background.

The best lighting for simulating natural light conditions would be metal halides. I don't think actinics will be very helpful since the dominance of the blue-spectrum doesn't become apparent until after several meters.

Will there be shifts in water-levels, depicting low and high tides in these systems or identical set-ups of both?

My guess is that a 6500K bulb should represent low-tide, and 10,000K for high-tide.

 

[Len]

Hey Jon,

Be prepared to get a HUGE chiller and HUGE electric bill. As for lighting a tidepool, most tidepools are exposed to intense sunlight most of the day and so I'm not sure why you'd like to dim the lights. Any lights would do, and if you can use sunlight and still maintain the low temperatures, this is perhaps the best, most natural option. Otherwise, a full spectrum bulb anywhere from 5500K to 10000K would work well.

Actinics were designed because studies demonstrated choraphyll A is most efficient at 420nm (actinic's wavelength). People just adopted this knowledge over to reefkeeping where many organisms are photosynthetic as wel.

 

[cdeakle]

[No message]

 

[Playdope]

Len,

Just to clarify ... no actinics on these tanks.. just 5500k ==> 10000k, yes? Which of the two is closer to daylight?

Do I need metal halides to produce the same light that is above the tidepools of Northern CA? If not halides, which type of lighting would be best for this type of setup?

I may have forgot to mention that this entire setup of tanks are in a coldroom (+-22 deg. centigrade) - so a huge chiller may not be neccesary.

Jon

PS> This isn't a system in my house. I have been appointed to help design the tidepool system at Sonoma State University. They asked me to research, and I knew you guys would have some great info to toss in.

 

[hdtran]

The sun approximates a black body radiating at 6000 K.

Can you do this outside? Then, no extra lights necessary...

 

[Anonymous]

Len,


Do I need metal halides to produce the same light that is above the tidepools of Northern CA? If not halides, which type of lighting would be best for this type of setup?

./quote]

In short, yes. I sent you a PM regarding some of these issues tool. Stick with one tank, and do that one tank right. You need losts of light, lots of O2, and low temps.
If you can stand to be in the room, you need a chiller.

Jim

 

[Playdope]

Jim,

"PS> This isn't a system in my house. I have been appointed to help design the tidepool system at Sonoma State University. They asked me to research, and I knew you guys would have some great info to toss in."

The school wants a large multitank tidepool setup. So far they have planned for the setup to be in a cold room, and they have told me they will add a chilling device if neccesary.

As for simulating daylight over the tanks... halide seems like the best option. Ideally, how high above a tank should a halide be hung so that it will not add a significant ammount of heat. There will be no canopies, volume is not a problem, so several large fans could be used if neccesary.

Thanks,
Jon

 

[Anonymous]

You need losts of light, lots of O2, and low temps.
If you can stand to be in the room, you need a chiller.

Lots of O2 for a tidepool tank? Stagnent for hours on end, reaching in the upwards of 80 degrees in the summer? I've done room temp tidepool tanks with excellent success, and with very low amounts of water movement.


For the metal halides you could use Sun Systems vented hoods and simply vent all the heat away.

 

[Anonymous]

We keep several coldwater intertidal inverts from Bodega Bay here at UCD. There are some in walk in refrigerators, some in tanks with chillers. We keep the temps at about 55 F, and light them with 6500K about 10 hrs a day. You may want to sync the lights to the hours of natural daylight but it's not necessary. It's also not necessary to vary the water level, at least with sessile inverts like gorgonians, anemones, etc. We *do* provide surges at irregular times during the day at around what would be "high tide". FWIW, we really don't do any kind of acclimation when moving animals from one tank to another. The temps and salinity are around the same so we just drop them in. Intertidal animals are generally very hardy.

I don't think O2 is much of a concern either, especially in such cold water. If you have a skimmer that should take care of any problems. A foot or more above the tank for the lighting should be enough to dissipate the heat with fans.

 

[Playdope]

Many thanks for the response! What kind of lighting do you use over your tanks at Davis?

Jon

 

[Anonymous]

Jon,
IIRC, we use 6500K lights on almost everything. On the larger tanks we have MH, on the smaller tanks we have PC.

If you provide me with a list of species that your school plans on keeping, I can try to find a care sheet that we use to keep them if we keep the same species.

 

[Anonymous]

You need losts of light, lots of O2, and low temps.
If you can stand to be in the room, you need a chiller.

Lots of O2 for a tidepool tank? Stagnent for hours on end, reaching in the upwards of 80 degrees in the summer? I've done room temp tidepool tanks with excellent success, and with very low amounts of water movement.

Yes but that's like saying I kept a reef system with little water movement and 32w PC's. There are corals that will thrive in these conditions, others that will not.
Not all the tidepool critters will survive in the conditions you describe, which is the high intertidal. Furthermore, nothing lives in stagnant water. In the low and mid intertidal you have mucho O2 and H2O exchange! A room temp tidepool will work with some organims, not with others. Next time you visit the tidepools, pay attention to the zones, and what organims you see living in each. The small 80 degree ones are lacking the diversity of the larger, colder ones lower in the intertidal. Abalone, anemones, chitons, and many other critters will not survive in a tank lacking the proper parameters.
Shore crabs will live in anything, including tropical tanks.
In order to insure that everything survives and thrives, things need to implimented as I described.
As far as the height of the halides, that depends on the wattage. The higher the wattage, the higher you can suspend them and get the tank away from the heat. 400w moguls or 250 HQI's are in order, especially if you plan on keeping Anthopleura xanthogrammica (giant green sea anemone). If you don't plan on keeping these guys, but still want decent macro algea growth and such, you can get away with less, but I would er in favor of the system, not your wallet if you can help it. Easier said than done I know.
Matt your comment about 02 levels in cold water is a good point. I would prefer, for the purpose of a display tank, to set up a surge device to provide at least 2 zones though. For interests sake if nothing else.


Cheers
Jim

Jim

 

[Anonymous]

PD, sorry it took such a long time, but I'll try and highlight some of the more interesting animals we have and some of their care. I decided to post it in the forum just in case anyone else should ever search for or need this info.

Two of the ID books we have are:
Intertidal Invertebrates of California, by Morris, Abbott, and Haderlie.

Guide to Marine Invertebrates: Alaska to Baja California by Daniel W. Gotshall.

In the Phylum Cnidaria, we collect:
The hydroid Tubularia crocea
Some anemones, probably Anthopleura spp.
The corallimorph Corynactis californica (I think so, anyway. If not it might be Balanophyllia)
Some gorgonians in the genus Muricea

In the Phylum Polychaeta we collect:
The tube worm Salmacina tribranchiata
The sabellid Myxicola infundibulum
Other various 'bristleworms'

In the Phylum Mollusca we collect:
The snail Lithopoma undosum
There are some pics of Navanax inermis and Hermissenda crassicornis here:
http://reefs.org/phpBB2/viewtopic.php?t ... ht=navanax
and a pic of Flabellinopsis iodinea here:
http://reefs.org/phpBB2/viewtopic.php?t ... ht=iodinea
These are the only sea slugs we collect on purpose.
We also have an Octopus bimaculatus right now. Rob Toonen raised the babies of a gravid female here a few years ago.

In the Phylum Arthropoda we collect:
Lots of different hermits
The globe crab Randallia ornata, a very neat little creature.
The kelp crab, either Pugettia spp. or Taliepus nuttalli These guys only eat kelp as far as I know. Someone on campus regularly collects kelp that we feed them.

In the Phylum Echinodermata we collect:
The very common white urchin Lytechinus anamesus
The heart urchin Lovenia cordiformis
The sand star Astropecten spp. Don't keep these with any "live" sand if you want it to stay that way.
Various brittles.

 

[Playdope]

Excellent response Matt! Thank you very much for putting that list together. We are still putting together ideas for the setup over here. We are leaning towards using power compacts over all of the tanks.

Out of curiousity Matt, how are your tanks plumbed in Davis? Do you have a rack-type system encorporating several small tanks? We will most likely be doing a lineup of 10 gal. tanks, but I am still trying to figure out how we could calculate which pump(s) should be used to circulate water through each system. I am thinking for each row, we could use an Iwaki of some sort... but lacking experience in working with multi-tank linked setups... I am not sure how large a pump will be neccesary for each network.

What kind of regular maintenance is performed on the tanks over there (water changes, testing, feeding, cleaning of equipment, etc..)?

Many thanks,
Jon

 

[Anonymous]

Jon,
Most of our tanks are simply for holding the animals, not display. They are shallow, about 6", and about 10' long by 2' wide. There are 3-4 stacked on top of each other. We have (I think?) 9 of these for the biology classes, and 10 more in a cold room that hold lots of kelp and other organisms used for research. (One prof here, Rick Grosberg, is doing some work on a small cnidarian that only lives on a certain type of snail shell. The grad students get to count each pinhead sized polyp on hundreds of snail shells...FUN!) Water is pumped to the top one, flows down a standpipe into the one directly below it, which flows into the one below that, etc. They are subdivided into separate containers with plastic eggcrate and zip ties.

For most of them the simple flow from the standpipe is enough. On the cnidarian shelf we have a couple extra pumps on a wavemaker for extra flow. There are also 3 100 gallon tanks with surge devices for some of the larger intertidal animals. These tanks are like standard reef tanks, except colder.

How are you going to connect the tanks together? Are they acrylic or glass? For things like snails, crabs, etc. a turnover rate of 5-10x is probably advisable. For corals I'd treat it like a reef tank and use either a surge or SCWD or wavemaker along with at least 10-20X turnover.

As far as maintenance goes, we feed GPs and DTs every day for the filter feeders and target feed everything else. We have a little recipe for the urchins with agar in it, I'll have to find that next time. I think they test for nitrogenous compounds every week or something. We have a thermometer/pH digital readout on every tank. They test for SG occasionally. All these values aren't super crucial in any case...you'll find soon that intertidal critters are super hardy. It is very important that you put ball or gate valves (I prefer gate) and unions on pumps, chillers, anything that you may need to remove and service, and I strongly suggest creating bypasses for chillers as well. We have some very old chillers/pumps, and it seems like they're always breaking down. It would be very nice if I could turn a couple valves and simply remove the chiller while still keeping the flow going. Unfortunately it's not that simple.