Brine Shrimp

[Kace]

Hello, I am doing a science project involving brine shrimp. I need to raise brine shrimp in differing pH's for about 3 weeks. Currently, I am confused as to how to properly maintain the shrimp's aeration. I was initially thinking of using an air pump and a lot of tubing to aerate all 15 of my containers, but many websites have been suggesting air stones. I was hoping to purchase a singular air pump and use that throughout the duration of my experiment instead of having to buy numerous air stones for each container. Or do I need both an air pump and air stones? Regardless, any advice for culturing brine shrimp is much appreciated.
Thank you very much.

[donnahardy2]

Hi Kace,

Welcome to Science Buddies!

This sounds like an excellent project! I have never hatched brine shrimp, but in checking various sources, all mention the requirement of oxygen for hatching brine shrimp. You can provide the needed oxygen with an air pump, and you could also add air stones. Here is a source that suggests keeping the eggs suspended in a column of water with air bubbles’ the directions here are very detailed:

http://www.brineshrimpdirect.com/c90/ha ... -c169.html

The oxygen is one of your controlled parameters, so you should try to provide as much oxygen as possible, but keep it consistent for all samples. If you want to avoid the extra expense of air stones, then omit them for all samples. You should record the percentage of eggs that hatch and if the percentage is high in your control sample, then you have enough oxygen; if it is low, then you may need to increase oxygen for all of the samples, so this is not a limiting factor.

pH is your independent variable. What is your dependent variable in this experiment? What other parameters will be important to control (and document)?

Donna Hardy

[Kace]

Hello there, I am doing a science project on the effect of ocean acidification on brine shrimp. I decided to try and mimic what is actually happening with ocean acidification as much as possible. I used this graph for my pH: http://www.global-greenhouse-warming.co ... jpg?72f992 . And I rounded the points to 8.2,8.1,8.0,7.9, and 7.8. I plan to decrease the acidity of the water that the shrimp live in as they mature to try and mimic actual ocean acidification.I have a couple questions I would be very grateful if you answered them:
1) Would I be able to make a solution with such specific pH?
2) How should I lower the pH of the water, I know in reality Co2 dissolves in water to form carbonic acid which makes the water acidic but I am unsure as to how to get my hands on carbonic acid. Perhaps I could used plain carbonated water instead?
3) If I cannot get carbonic acid, is there another acid I use to make the water acidic that best matches the natural process that occurs in the ocean? If there is not any acid that would qualify can I use vinegar?
4) Also, I was going to have 5 different trials with each trial only decreasing by .1 increment. Is that too small of a decrease? Or should I have one trial grown at 8.2 and decreased to 7.8? I believe blood pH in humans must stay at 7.4 and even the slightest deviation might mess up the body so maybe the first idea would work better?
If you have any other suggestions for my experiment I'd really appreciate it.
Thank you very much.

[MadelineB]

Hi Kace and Donna,

I noticed that Kace had posted a similar question in the Physical Sciences forum. I moved that post to this thread to keep the questions and discussions about this project together.

Madeline
Moderator

[donnahardy2]

Hi Madeline,

Thanks! It's always best to keep all inquiries on a project together.


Hi Kace,

A standard pH meter would be best to use to adjust the pH of the water. pH paper can be used, but is not as accurate and would not be good for detecting small pH shifts. .

Do you have access to a lab with a pH meter? You will need to make sure the pH meter is calibrated with pH standards before you use it.

You will need to mix the entire water sample very well (a container with a stir bar works well) and add the carbonic acid or sodium carbonate to adjust the pH. You can use carbonated water as the source of carbon dioxide as long as there are no other ingredients in the water. You can also get some dry ice the let it sit in a bottle of water until it disappears, and tighten the bottle cap just as the dry ice is disappearing. This would give you pure carbonic acid.

You should also be able to just add dry ice to the water and measure the pH while mixing until the desired pH is reached. It would probably be best to add the dry ice to the water a little at a time and stir well.

I have never tried this, but you should also be able to put your water sample in a closed container that provides a large surface area of water with some air space. If you then burn a candle in the closed container the carbon dioxide produced by the combustion will dissolve in the water and lower the pH. This would be a slow method, but would work.

You should definitely try to test several (at least 5) pH points, although I’m not certain about the range. From the few sources I have checked, it appears that brine shrimp have a range from 6 to 9, so you may not need to use 0.1 pH increments. Please do read as many references as you can find about the pH range of brine shrimp and then choose 5 points within that range.

Please post again to reply to this message if you need more help. It’s really great that you are spending some time to think about the details of your experiment before you start.

Donna

[mako1596]

HI am also doing a experiment testing salinity they hatch best in and I used 2 grams of brine shrimp and had 4 diff containers with different salt amount the one that worked best was 5g of aquarium salt per liter.
Hopes it helps.

[RachelHope]

Hi "mako1596" - I am also doing a Brine Shrimp/Salinity science project. I was wondering if you used a filter or air pump in your containers?
Thank you!