It's all in the details....

[BallAquatics]

I can't remember when I didn't hatch a batch of baby brine shrimp (bbs) on a daily basis.  My problem here of late, was that my hatch rates had been falling and I was at a loss as to the reason.  Well after checking all the obvious causes without any improvements I though perhaps a refresher course was in order and I went back to bbs 101.

Well, long story short, I was adding too much salt.  After years of mixing up a batch every day I had become rather lackadaisical in my measurements.  I was using something close to a litre of water and a couple heaping table spoons of salt per batch.  Once I got a grip and started measuring exactly 1 2/3 table spoons of salt to a litre of water all was well again.

It all has to do with the way that things work in nature.  Normally the Great Salt Lake is all but saturated with sodium chloride and other salts. But each year, for a few short weeks following snow melt, vast quantities of freshwater come pouring out of the Wasatch Mountains into the Great Salt Lake. Since freshwater is lighter than brine, the snow melt forms a temporary freshwater "lens" floating on the surface waters. When salt concentration drops below about twice the brininess of seawater, to less than 70ppt, the cysts hatch.

Even with the rising costs of high quality eggs, bbs is still a real bargain for the amount of food you get for the money and time spent.  A pound of Grade 'A' eggs is going for around $47.00 and I get my salt at Wal-Mart for .50 cents.  At those costs, I can produce 255,000 nauplii (baby brine shrimp) per gram of cysts for around $0.12 cents a batch.  A great value in my book.

Dennis

[Mugwump]

Amen, Dennis,,,,bbs, and micro worms, for pennies,,,and getting a multitude of really good fry food...

[LizStreithorst]

I use a tablespoon of salt to 2 liters of water, more or less.  The salinity can vary a good bit from that either way.  With the amount of salt you were using you were salting the poor little bs eggs to death.

[BallAquatics]

I pretty much use the same recipe that's on Brine Shrimp Direct......  it was the "more or less" part that got me into trouble.

Dennis

[LizStreithorst]

And your wife and I have been calling you Mr. Spock?  Even Spock would have figured out that much salt was way too much more  

It's nice to know that I'm not the only smart person here who does stupid things

[Mugwump]

Ahem, I use 2 tblspns too.....hydrometer says that I'm right on the money....Liz, have you tried a little 'extra' salt?...you could be missing out on a better hatch rate...

[LizStreithorst]

They hatch just great for me.  I generally go with more salt because the tablespoon gets heaping when I pour the salt into it.  So may be I'm using a tablespoon and 1/4.  Heck, it works great for me.  I'll experiment with 2 tablespoons of salt to 2 liters when I put on my next batch later tonight.

[BallAquatics]

Even Spock would have figured out that much salt was way too much more  

LOL  Yep, that was the whole point of the post.  Little by little as time went by my, sloppy measurements lead to using too much salt and failing to trigger the hatch response in the cysts.   

Dennis

[BillT]

I had a similar problem with my smaller BS hatcher (I have a large one (6 liters) and a smaller 2 liter one).
After trying a bunch of things i could only make it work well by using salt mix and RO water as opposed to the dechlorinate tap water and rock salt with baking soda I was using.
I do know its not due to amounts because i measure everything.

Don't know why.

[LizStreithorst]

I always use straight tap water to hatch my BBS.  Some Discus people even add a bit of Clorox but I've never done that.  The theory is that the chlorine helps break down the shells and puts a hurtin' on some nasty that the BS carry.

[BallAquatics]

Same here, my well water is hard enough that I've never needed to add anything other than salt.  Mike Hellweg also recommends a couple drops of Clorox in his book.  I used it for about a year and I do think it helps keep the hatchery cleaner, never noticed any difference in hatch rate though.

I've always heard that because of their briny native haunts, Artemia are absolutely guaranteed not to introduce any parasites into a freshwater system.

Dennis

[BillT]

You can use bleach to decap they if you leave them in there long enough.
Then you can put your decp'ed eggs into saturated brine which sucks the water out of the eggs osmotically.
This makes the eggs dehydrated even though they are in the water and they can be stored in the frig that way for a week or more.

On a related note, there are a few zebrafish labs that are now using only rotifers to raise their fish. No BS.  They figure its cheaper to buy the algae paste from Reed Mariculture rather than buying new brine shrimp eggs in the huge amounts they use.
Some big places might use a can or two a week.

I've always heard that because of their briny native haunts, Artemia are absolutely guaranteed not to introduce any parasites into a freshwater system.

Largely true, but there is a bacteria (found sometimes on BS) that can infect fish. Bleach would largely eliminate this if it were present.

[BallAquatics]

Looking at the Reed Mariculture website, I'm very tempted to try to culture some rotifers, but I don't really want to have to deal with all that saltwater.....

What I'd really like, is to get a starter of Moina.   My old stand-by for Moina starters, Alex Tran down in Dallas, says he's out-of-stock.   

Dennis

[BillT]

I have Moina if you want some Dennis.

I also have a separate line of Moina that I have been adapting to more brackish water of 8-10 months.
I am now testing them in 1.05 gm/L salinity. They started at 1.03 and were not able to breed at higher salt levels.
They can now breed at 1.04. My goal is to get them up to 1.06.

[BallAquatics]

I have Moina if you want some Dennis.

They would be very much appreciated Bill.....  NOT the saltwater ones though   

Shoot me a PM about the costs and we'll get something cooking.

Dennis