Intertidal aquarium...does anyone do this?

[TheTyro]

Alrighty, I've been scouring the internet the past two days for information on a very specific setup. I have some critters from the Normandy Beach Park here in Washington State. The majority of the creatures are shore crabs and small hermit crabs, along with some sea lice, small sea snails and some live barnacle that was stuck on a clam shell. I collected a bit of sand, water, shells and seaweed and have it in a small tank. I'd guess it's about 5.5 gallons?

I know this sounds kind of dumb, but I plan on just going to the source (Ocean) to collect water every so often to refresh the tank. If this is a terrible idea then I will do it traditionally. I'm kind of scared posting this here because I feel like an idiot trying this with so little background experience...it's not a marine reef aquarium and it isn't your "hermit crab" setup either. I wanted to pick relatively hardy animals that live in that specific stretch of beach that also had a freshwater creek/outlet running right beside the ocean. I have found about three various, vague guides on maintaining animals in this zone but nothing specific as specific as what I am trying to do.. Though they are based on the Oregon or California coast rather than Washington Coast- COLLECTING OREGON MARINE INVERTEBRATES, by Joe Middleton

http://www.bms.bc.ca/resources/animalcare/sops/CRAB SOP Mar 08.pdf

none of them specify long term care though.

I am curious about the sea-weed and algea especially. The species of crab I have eat algea, so I figure I'm going to have to have a light that will allow it to grow a little bit, along with the larger seaweed, I need to find out the species of seaweed though. I gathered stringy green types anchored to pebbles that are sometimes exposed to the sun and air, along with some free floating broader shaped green seaweed that glided to and fro in the tide, and also some other anchored reddish/purplish tinted seaweed.

I do have a pump with a filter going and I have been feeding them betta fish flakes ( temporarily if anyone can tell me it's not good for them) on the advice given in the article about crab care saying it should be a good source.

Here are some ultra crappy web-cam photos I just took.

For reference, I am experienced in keeping true spiders and other invertebrates, this is my first foray into aquariums in general. If this sort of thing isn't really feasable to do then I'll return the crabs to the beach.

 

[Kurt_Nelson]

What you're talking about is a "cold water marine aquarium". Google that term and you should find some stuff.

The main issue that makes these types of setups tough is water temperature. Room temperature is too warm for these critters, as you're well aware if you've ever dipped your toes in the water there at The Cove. You'll need a chiller to keep the water cool.

The other main issue you've already encountered - a lack of good information. Not many folks keeping these types of tanks, so you're kind of on your own when it comes to figuring things out.

Is it feasible for a first-time aquarium adventure? Guess it really depends on the type of person you are. If you're looking for a "learning experience", I suppose you're on the right track! But if you want a good shot at keeping a saltwater aquarium without having to learn everything on your own, I'd go with a more traditional tropical reef setup.

I normally don't point people toward other forums, but you might want to register over at Reef Frontiers and check them out. There are a LOT of folks over there from the Puget Sound area and I've seen threads about cold water tanks pop up from time to time on that site.

 

[TheTyro]

Thank you for the response! My temporary solution for maintaining a low temperature is keeping my windows open and running a fan over the water. It's already cooled down a lot! I'll probably pick up some insulating foam to stick on three of the four sides of the tank to try and keep the temperature from fluctuating too much too. Until I can aquire or make a chiller, anyways.

I'll be sure to check out the forum and google those key words, thats exactly what I was needing. I just didn't know what to look for!

My biggest question now is lighting. Since I have live seaweed, and an article about cold water marine aquariums mentioned full spectrum flourescent lights, what would be best for what I'm doing? I want algea to grow. There are so many different light types, I'm a little overwhelmed! All I know is since the tank itself is small, it'd have to be about 12 inches long.

 

[johnmaloney]

strawberry nems are easy to keep in that kind of tank, look cool and spread like wildfire. you might want to check them out. Cool tank, do you have the tides on a timer? I wanted to do that, I figure two drains, when the tide is "high" a second pump kicks on that overpowers the first drain until it reaches the second higher drilled drain...then it turns off at the ebb tide.