The Easy Bleach Method
For sterilizing seawater of average cleanliness, this protocol will yield water of acceptable sterility and quality for most microalgae (greenwater) and larval culture.

**Be sure to familiarize yourself with proper chemical handling techniques before attempting these procedures. Always wear protective goggles and gloves when handling any chemicals**

1.  Collect a known quantity of water to be sterilized.  If water is turbid, it may be necessary to prefilter for clarity.  This can be accomplished by dripping the water through a few coffee filters.

2.  Add 0.5ml unscented laundry bleach per liter of water.

3.  Seal the vessel and swirl the media so that all internal surfaces are wet.

4.  Allow the vessel to sit at room temperature for at least 6 hours, preferably 12-24.  The vessel may be stored for long period of time with the bleach inside, provided the vessel remains uncontaminated.

5) Prepare a 1M stock solution of Sodium Thiosulfate.  The most commonly available crystalline form is the pentahydrate, and should be added at 248 grams per liter.  This solution may be filter sterilized or autoclaved to ensure sterility.

6.  To de-chlorinate the water, add 0.1ml of 1M sodium thiosulfate per liter of water.

7.  Aerate at least 2 hours.

8.  Confirm that no residual chlorine exists before using the medium.  Dip tests for pools work well, as do the DPD reagent available in convenient liquid or powder pillow-packets.

Acid Sterilization

**If you are not familiar with the safety hazards associated with handling concentrated acids, DO NOT attempt this method**

1. Collect a known quantity of water to be sterilized.  If water is turbid, it may be necessary to prefilter for clarity.  This can be accomplished by dripping the water through a few coffee filters.

2.  Add sufficient hydrochloric acid or muriatic acid to reduce the pH of the solution to 3.6.  The amount needed will vary depending on the concentration of the acid stock, the initial pH of the water, and its buffering capacity, which may also be affected by residual calcium deposits in the vessel.  A good starting point for muriatic acid (about 32% concentration) is 2ml/L.

3.  Confirm pH with a pH meter or narrow range test strips.

4.  Swirl the sterilized solution so that all internal surfaces are moistened.

5.  Allowing a sufficient sterilization time (2-4 hours).

6.  Return the pH to normal with sodium bicarbonate (baking soda).  A good starting point is 1/8 tsp/L.

6.  Confirm pH is appropriate for culture with a pH meter or narrow range test strips.

After receiving so much interest from our creature feature on breeding Pom Pom crabs, Lybia tesselata, we’ve decided to make these a regular feature! Unlike our first creature feature post, we will present a species and provide an “aquaculture fact sheet” that summarizes the species and what is known about their care, captive breeding, and larval rearing, as well as any interesting information and photos that we have picked up in our rearing attempts. We hope that this will become a nice quick reference that aspiring aquaculturists can use to jump-start their successes. If you have any species you would like to see featured, please let us know. Thanks for all the suggestions and support we have received already!

We wanted to introduce everyone to a new species we are working with at AZaquaculture - the Pom Pom Crab, Lybia tesselata. Many of you are probably familiar with these odd little crabs, but they are just so unusual we had to share them with anyone who hasn’t encountered them.
Plus, they are SO photogenic!

Probably their most distinctive feature, the feature from which they derive their name, is the appearance of “pom poms” held on a pair of their legs. The pom poms are actually a pair of anemones from the Genus Bunodeopsis. Pom Pom crabs use these stinging anemones as a form of defense, assuming a boxer’s posture in response to threats. Even more remarkable, as the crab molts, these anemones must be moved from the old exoskeleton and mounted to the new chelipeds! No wonder these are a favorite organism for reef aquarium owners.

As you can see clearly in the picture below, this specimen of Lybia tesselata is carrying a fine clutch of eggs along the pleopods. This picture was taken approximately 24 hours after the eggs were deposited. With such odd looking parents, we are all quite excited to start working with the larvae. Check back often, we plan to update with lots of pictures as the project progresses.