Angelfish Fry Dying

Question
QUESTION: Hello,
I am fairly new in raising angels.  I have two pair of Koi angelfish that are laying at 10-14 days apart.  This is my 6th batch of eggs.  I have no problem artificially hatching the eggs with less than 5% loss to fungus.  Only a half dozen die before becoming free swimming.  This is where I have the problem.  I am using city tap water conditioned to be soft with a fairly high ph around 7 heated to 80 deg with a sponge filter and bubble wand.  I move them into a 2.5 gal rearing tank and begin feeding baby brine shrimp and fry powder when all become free swimming in a cloud.  Everything is great the first 3 days.  No problems with 90% water changes daily.  Fry are live and active.  Few lost.  At day 4 after free swimming, large losses of fry.  Day 5-No fry alive.  What is possibly wrong?  Please help.

Jacob


ANSWER: Hi Jacob,
 Are they actually eating the brine shrimp? -- their bellies will go quite orange if they are.

-- Ron
  rcoleman@cichlidresearch.com
  Cichlid Research Home Page <http://cichlidresearch.com>


---------- FOLLOW-UP ----------

QUESTION: Yes, I use fresh hatch less than 2 days old baby brine shrimp (BBS) that has been rinsed in fresh water.  I place a cloud of BBS in the tank with them.  Only a few remain after 10 min.  I feed once in the morning, twice at night.  Bottom is syphoned with 1/8" air tube to remove any debri and uneaten BBS.

ANSWER: Hi Jacob,
 It sounds like you are doing the brine shrimp right but just to be sure:  they are alive when you feed them, right?  One mistake that people make is feeding dead hatched brine shrimp: once they die in the shrimp hatchery they quickly become really toxic and you should never feed dead newly hatched shrimp.  
In other words, when you put the little shrimp in with the baby angelfish, the little shrimp should still be swimming.  Also, the little brine shrimp "egg shells" are toxic and shouldn't go in to the angelfish tank.

-- Ron
  rcoleman@cichlidresearch.com
  Cichlid Research Home Page <http://cichlidresearch.com>


---------- FOLLOW-UP ----------

QUESTION: Yes, I check the shrimp before putting them into the tank to make sure they are swimming.  I take the shrimp with a syphon from near the bottom where all the eggs shells float to the top.  The are rinsed through a strainer with paper towels as the filter.  They are placed in with the fry which visibly attack the shrimp eating like little pirahnas.  The shrimp still swim and are removed after 15 min alive.  Water change 90% daily after the last feeding of the day.  Bottom syphoned to remove all particles.  I just lost 200-300 fry yesterday in one day that are 10 days from the first wiggler stage.  One pair has been cleaning and are ready to lay again today.  I am at a loss.  I do not have a clue what is wrong.  It is really weird.  All this happens in a matter of 12 hours.  One day energetic hungry fry the next all dead.  No apparent reason.  No change in conditions, no ammonia spike, no ph spike(tested on the dead take last night).

Answer
Hi Jacob,
 That is very peculiar.  Several possibilities could be happening.  There could be some infection which is hitting only once the fry reach a certain stage (unlikely).  There is also the possibility that a lethal gene is being expressed at that point in development.  For most fish this would be very unlikely, but most angelfish have been severely inbred making this much more of a possibility (though still pretty remote).  

 If you want to try something, kick the heat up in the fry tank to about 85oF the next time and let me know what happens.

-- Ron
  rcoleman@cichlidresearch.com
  Cichlid Research Home Page <http://cichlidresearch.com>