bent backs in A. ephippium larvae

last week i hatched a large nest of fire clown larvae . I had pulled the nest on day 7 for artificial incubation but only a few larvae had hatched that night . the 4 or 5 that hatched looked healthy and normal . on the 8th morning after seeing that i didnt get a complete hatch i did a methylene blue dip and set the nest up for hatching that night.
upon my return the next morning i had a great hatch 100% about 300 -400 larvae!
as the larvae started coming up from the bottom i noticed about half of the larvae had bent backs ( like L shaped larvae) . some were swimming in circles . i have seen some larvae right after hatch have a mild bend that corrects itself in a day or so in other batches ( from other pairs) but never this many with extreme bends. so i set them up with rots and green water for the day .
that night i came back to about 90% die off !
the handful of larvae i still have from this batch is hitting meta . most are normal but 2 of them have bent backs but swim and hunt normally . 
i was planning on culling but i am curious to see what happens .
i am not sure as to the cause of this .
i havnt made any dietary changes with this pair and all larvae from them in the past have been straight as an arrow.
the only thing i can think of is i had the aeration over the nest ( on the second night of hatching ) turned up a little higher than normal .
could this have been from bubble trauma? 
what do you guys think?
 

Was the nest on a tile? At any time did the tile fall, egg side down?
 
When I first started, I didn't have a spawning pair, so I got a nest from a friend's pair.  They laid on a tile.  I tried to prop the tile up in the bucket with the airstone under it for the ride home, but the darned thing flopped over several times before I got home.  That batch hatched out, and nearly all of them died, bent backs all of them. I think its a crush injury, or at least it was for me.  I'm not saying this happened to you, just relaying my experience.  This is one way it can happen.

interesting kathy .
this nest was in a 6 inch clay pot but it sounds like trauma can definitely cause this issue .
i have another ephippium nest to hatch tonight so ill run the incubator a little slower .
i have been hatching in a BRT and it makes it difficult to see the bubble rate and coverage of bubbles over the nest .
its kinda all guesswork .
it would be nice to be able to gauge and record the flow rate out of the air pump so its not a little  different every time i hatch .
any tips on how i could do that?

Was the nest in the inside of the pot? It is hard to get bubbles to stimulate flow in this case.  That said, I've had nests hatch completely when the bubbles never touched them, but just caused a current of water, enough to make them move.
 
Typically, my fish spawn over the inner rim of the pot in a long nest that covers a third or more of the circumference. In this case, I have been setting the pot on its side so that the eggs are on one side or the other, and the airstone sits inside the pot on the bottom. I try to get the nest so that there are no eggs on the bottom of the circle near the floor of the tank, as that is where the flow will be the least. I've noticed when I do this that the eggs still move regularly, and that is what I am aiming for.
 
Depending on the size of the pot, you may wish to experiment. Can you get the eggs to move regularly if you stand the pot up on its base and drop the airstone to the bottom? If that works, it may be the best bet, considering that you are working with a BRT, and cannot observe from the side, as with a glass tank.

duplicate post

yeah this pair likes to lay on the ceiling of the pot about half way in .
i have been hatching by laying the pot on its side with a floppy bubble wand affixed to a template that fits snug into the pot under the nest . the bubbles hit the eggs .
ill try sitting the pot upright to see what kind of flow i get . in the past when wouldnt get a good hatch rate  i thought it was because some eggs werent being touched by bubbles . maybe whats really going on is the eggs that dont hatch are just being hammered by bubbles . my incubating device puts out pretty fine bubbles so i didnt think it was a problem . 
i am a little nervous about trying somthing new with this nest because its the biggest nest ive had from this pair approx 400 - 500 eggs . but ill give it a go
 

Good luck, and let us know!

well i have had a couple bad hatches since my last post in this thread.
the last try i had the pot sitting upright on its base with an air stone on a piece of rigid airline 
set so the bubbles were not touching the eggs but running about 1/4" away from the eggs .
after watching the male doing his daddy duties . i realized that he doesnt aggressively fan and mouth the eggs like my ocellaris male does .so i was thinking that maybe i shouldnt have the bubbles hitting the eggs like i do with the ocellaris nests. 
this didnt work . only 5-6 hatched and the rest fungused even though i had dont a 10 minute methylene blue bath and sterilized the brt before incubation .
so it seems there is a very fine line between not enough and too much bubble contact. 
i wish there was a way to reference the ideal rate . 
could anyone link me to a video of their incubation technique?
 
 

Getting the bubble rate and orientation "just right" is a bit tricky. I usually let the bubbles contact the eggs.
 
I find that tiles are much easier to aerate than pots since you're working with a single plane rather than a curved surface. 

http://www.fishtalpropagations.com/#!home/mainPage
"Making captive breeding easier."

Yes, I think its fine if the bubbles hit the eggs and move on up.  I think the trouble comes when the bubble stream is perpedicular to the surface to which the eggs adhere.  Then the eggs are getting hammered by the bubbles. If the bubble stream is parrallel to the surface the bubbles move the eggs, and keep right on going.  It may be gentler.

 
I would agree with Kathy.  I do let the bubbles hit my eggs and pretty much always have as my clowns always lay on the inside of the pot like yours do.  I have found an airstone made by rena I believe it is that works the best IMO.  The bubbles seem to be fine enough not to damage the eggs but big enough not to stick. I have tried a lot of different airstones and that one works best for me.

I found a link to the ones I use.  They last forever.  I have both the 2" & 4" ones depending on the pot and clutch size.
 
http://www.rena.net/Produ...duct.aspx?ProductID=99
 
 

i have found what i believe to be the problem with my incubation protocol .
i had been having difficulties getting good hatch rates and prior to last week i attributed it to inadequate bubble flow over the nest . it was either too much causing bent / broken backs or too little allowing bacterial / fungal infection to run its course . 
  after a few weeks of trying to dial in my flow rate and experimenting with new protocol ( thanks to my clown pairs giving me lots of opportunity ) i have found that its not my bubble rate thats giving me problems .... ITS MY DISINFECTION DIP !!! 
methylene blue was not doing the trick ! 
MB was causing visible fungus to recede after dipping but by the time its visible its too late . i dont believe it was killing the bacteria that causes tissue necrosis that the fungus was then growing on . 
kinda like treating symptoms and not the root cause .
five days ago i pulled an ocellaris nest and played around with a new dip formula .
IT WORKED !! 
i had a 95% hatch rate the first night and the following evening after a preventative dip for good measure the other 5 % hatched healthy!
some had even  hatched in the 2 1/2 gal dip bucket without aeration!
tonight i will be trying it out on my ephippium nest and will post the results .
 
 
 

And the new dip formula is:  Inquiring minds want to know!

This is an interesting idea. Personally, I've never dipped any of my clownfish eggs prior to hatching and I've only had one batch of A. percula (Picasso variant) that had a few individuals with crooked spines.

http://www.fishtalpropagations.com/#!home/mainPage
"Making captive breeding easier."

Sorry about the cliff hanger guys ..
well the dip is far from a new formula to the aquaculture community .
but it is new to me and i havnt found any info on its use in clownfish rearing .
the dip is good ole H202 at 5ml per 1.5 liters broodstock water for 10 min .
its really interesting , i think it may soften or partially dissolve the outer membrane of the egg making it easier for the larvae to hatch . 
i have been using this dip without aeration in a 2 1/2 gal bucket .
if i pull the nest in the evening on the night of hatch and partially shade the bucket the larvae start hatching without any other stimulation . the larvae that hatch in the dip bucket seem unharmed by it and survive the transfer to the brt just fine .
its almost like hatching on demand !
the ephippium nest i hatched last night , i had pulled early in the afternoon long before they would have hatched in the broodstock tank as my light cycle runs 10am ON to  midnight OFF. this dip i didnt want them hatching in the dip bucket so i kept the pot sitting upright catching full light from an overhead T5.
after the dip i transfered the pot into the brt and possitioned it on its side while i was getting my other components in order and larvae started hatching ! this was before i even placed the air stone in the pot . 
so i went ahead and added the air stone under the nest on a much lower flow rate than i have ever tried before .. more larvae hatched within seconds .
next i covered the brt as per normal .
i had to run a few errands and when i got back 2 hours later i had a 100% hatch rate !!!!
this was a huge nest .. probably 400-600 by far the most i have ever seen in my brts .
 
 

on my next hatch ( this coming tuesday) i will take an egg sample before and after the dip to compare under my microscope to see what the dip is really doing to the eggs .
i have used H202 in  the past as a zoanthid dip to remove algae . this dosage is a bit stronger than i am using on the fish but it starts to dissolve the outer wall of bubble algae within a few min. i think it may be doing somthing similar to the eggs . 
i have never seen mass hatching like this with minimal to no stimulation .
it seems that if i use this dip in direct light it buys me enough time to get the nest into the brt . if i use this dip and partially shade the nest they hatch right away .
this is great for my purposes because i live across town from my fish room and it is always difficult to get there in the early morning before work to uncover and set up newly hatched larvae .
now i can get done what took a full night and two trips done in a matter of 2 hours !!
AWESOME
 

Glen, how has this been working for you in the following months? It certainly sounds like you are on to something.

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