My Method

by Chip Hannum

This is a brief outline of my particular methods for isolating eggs and preparing them for hatching. It has worked reliably for several generations and will presumably continue to work for many, many more. The technique is simple but it is a technique - how well it works for you is going to depend on your understanding of the instructions. Hence, I provide this as is with no guarantee as to your results.

Why do all this?

There is no overwhelmingly compelling reason for separating out pure eggs and mixing them with a measured amounts of specialised detritus. A small amount of dried gravel or sand containing eggs will usually work just fine. I do it for a number of reasons:

• It is extremely reliable, moreso even than commercial preparations because I’m not being cheap and trying to stretch my eggs as far as they can go.
• The detritus recipe that I use both inhibits bacterial growth and provides a source of nutrition for the larval triops.
• It is far more convenient, in my mind, to have a single jar of egg mixture where I can scoop out a single teaspoon and start a new generation at any time than it is to have a large amount of dried sand or gravel for the same purpose.
• It takes a lot longer to dry a tank of gravel or sand than it does isolated eggs.
• I like doing things the complicated way :)

Isolating Eggs

I raise my triops in a 5 gallon aquarium with about 5 - 6cm of small/medium grade river gravel (from the pet store). I use an undergravel filter which keeps the water clear and does not disturb the triops or harm the eggs in the slightest. After a couple of generations have done their thing in the tank (about eight to twelve adults total) I break down the tank completely.

I start by siphoning/scooping all the water out of the tank until it is a few centimeters above the gravel and then I pull the plants, undergravel filter, decorations, etc. out of the tank. I then tilt the tank at a slight angle and stir the gravel up with my hands, moving it towards the higher end. As quickly as I can, before things can settle, I scoop out some of the rather filthy water. I use wide mouth half-pint jars, but any shallow glass or bowl should work. Then, I head for the sink.

This next part of the instructions takes advantage of a few properties of the eggs:

• They’re lighter than the gravel but heavier than silt
• In their hydrated diapause state, they are nigh impervious to chemicals short of harsh alkalis and acids

I let each container of triops filth settle for about ten to fifteen seconds and pour off about half of the water in the container. I then refill each container with cold tap water and let that settle for ten to fifteen seconds. I pour half of that off and refill with cold tapwater, letting it settle for a bit, pouring half of it off, refilling, you get the idea. What you are doing is analogous to gold panning - the heavier triops eggs keep settling to the bottom of the container after a short while but the silt remains suspended in the water to be poured down the sink. After about four to six of these partial water exchanges the water in the container will be clear and there will be some stuff on the bottom: this is the triops eggs and small bits of gravel and woody detritus.

I pour off the water one last time, still leaving enough that I’m not pouring out eggs, and swirl that and let it sit for a bit. The swirling causes the eggs to collect in the center of the container where I siphon them up with a small syringe and transfer them to a shallow dish for drying.

I can repeat this process as many times as I want just by stirring up the gravel again. Ordinary tap water can be added to the gravel if you run out of water in the tank. In the space of a half hour or so I can easily collect several hundred to a few thousand eggs this way.

Once I’m satisfied with the haul I gently siphon off most of the water covering the isolated eggs and allow them to dry at room temperature for a few weeks before dislodging them from drying dish with a soft paint brush. I then perform a rough and dirty count and mix them with my homemade detritus (next section) at a ratio of roughly 50 eggs per teaspoon of detritus. I use one teaspoon of my egg mixture in approximately one liter of distilled water for hatching.

Homemade Detritus

The problem of hatching triops is that the water must closely mimic conditions found in their natural habitat. Without a suitable source of detritus or other water conditioning, larval triops usually die after a few days, often due to sharp increases in bacterial numbers. The most common way commercial kits provide a proper environment is through mixing the eggs with dried pond detritus which contains algal and protozoan cysts, provides disolved organic compounds in the water, etc.

Now, most of us don’t have a pond in our backyard for harvesting natural detritus but we do have a pet store in town. What I use for making homemade detritus is ground coconut shell (usually marketed as bark) which is sold in compressed bricks for reptile bedding. This stuff is great, a single $6 brick will let you make enough detritus to hatch triops for the next decade (at least). I mix the coconut bark with tank water from an established triops or other fish tank until it forms a thick mud. I then dry it in a food dehydrator, but it could just as easily be spread thinly in a baking pan and allowed to thoroughly airdry. That’s it.

The tank water provides the protozoan and algal cysts. The coco-bark leaches tannins into the water which both simulates the natural pool environment and inhibits bacterial growth. It’s also edible for triops which is a bonus.

End.