Another failure

[David M]

As of last night I was well on my way to my best results so far, I had 150-200 oc's at 10 days. This morning 90% are dead and the live ones look bad. They are paper thin, I'd go as gas as to say their bellies are sunk in. When I went to bed last night they had fat round bellies stuffed with bbs, CE and probably some of the Otohime I tried. I don't think it's water quality, ammonia is way below the typical levels. What happened????? I can understand them dying, I'm used to that, but why are their bellies shrunken?

 

[JHardman]

Did you see any of them die? What was the behavior before dropping? Anything that could point to bac infection or low O2?

 

[David M]

Lying on the bottom, spinning upward into the water column and then crashing back down. Some at the surface spinning. You can see food in the guts but they are collapsed. Looks like food packaged by one of those heat seal machines.

 

[JHardman]

Humm... If they over ate, or ate too large of a shrimp, they could have burst and that could account for the shunken belly.

Could be bad BBS. Did you feed anything else that same BBS? Notice anything with that? Keep in mind that older/larger fish maynot react as bad as these guys...

Bottom line you shouldn't be seeing massive overnight die offs like this. The die behavior sounds kind of like lack of O2. Is it possible you got a bac bloom or BBS consumed it? It the tank was on the edge with O2 saturation that could be it. Did you think to get a pH reading? (I know last thing on your mind, but worth asking).

 

[FishGuttz]

Fat round bellies... hmmm sounds like swim bladder disease. You are over feeding!! bbs are coarse little suckers. The bellies look like that because they are constipated with BBS.

 

[David M]

Bacterial bloom- maybe from the otohime? I just got it yesterday and last night was the first time I used it. Probably used too much but did not find a lot on the bottom this morning. Ahhh- sponge filter probably got it. That is the other thing I did different, added the sponge filter which I normally don't do 'til after met. There was a ton of unhatched artemia cysts (decapped) in there I wanted to remove.

Overfeeding- very possible, I am home this week (injury) and spent most of the day feeding fish every few hours thinking I was being "good" to them.

BBs- same bbs fed to post met fry at 3.5 weeks, 5.5 weeks, 6 day old bangaii's, 3-1/2 month old clowns and all my adult fish. However ALL of those are in the 900 gal recirculating system, only the larvae that died are in an isolated tank.


02- I think it's good, have pretty heavy air going.

I guess "if it works, don't fix it" applies. I have done OK feeding larvae twice daily up to now, all of a sudden with this batch I was feeding 5-6 times per day all weekend and yesterday. I never had this many before so I thought I needed more food

 

[Dman]

Ouch, that hurts.
My first thought was O2, whenever I've had massive overnight dieoffs it's almost always been due to O2 levels. But you've said there's plenty of air going, so that nixs that.
If it works, don't fix it motto is as good a place to start as any, and it could very well be the feeding. So it sounds like you may have answered your own Q.

 

[Kathy55g]

i think the hardest thing is to know how much to feed them. I can't be here all day, so while they are on live food, they get fed twice a day. How do you measure bbs?

This latest hatch is the biggest one I've dealt with and from different parents. The larvae are so different--they are not even the same color. They have yet to get that swollen belly look that always told me before that they had enough. Yet, they are growing, and not dying (very much), so ....

If it ain't broke....

Sorry for your loss.
Kathy

 

[oyvind]

I also had a 50% loss of my 10 days ocellaris yesterday, but unfortunaly I know why, I changed water to fast because I was concerned about water quality, half of them died in seconds, the other half was laying dead at the bottom this morning, a very sad day! Salinity in the new water was a bit lower than that in the tank, but I fear the speed of the change was the deadliest factor.

 

[Dman]

oyvind,
Another factor could have been ammonia toxicity due to different pH levels in the make up water. An ammonia binding compound like CloramX or Amquel could have headed that one off.
MTCW

 

[Peter Schmiedel]

@Dman,

do you always add the amonia binding coumpunds if you chnage water?
On my side of earth they are not known / used.

@David
I have in mind that we had a similar tread after changing to new food a few weeks ago? Does one remember?

 

[oyvind]

Dman
As Peters says that kind of stuff is difficult to bye here in Europe. Will try to be more carefull with water change with my new 2days old larvea this time. Last time (3 ears ago) I was breeding I didnt have that problem with losses around metamorfosis. Am co culturing rotifer and nanochlorepsis in the tank with the larvea and have not had ammonia in the tank at all this time. Difficult to buy live rotifers here in Europe so I have to start my roitfer culture from cysts from USA (Florida Aquafarm) and have had some problems whith this this time. But it seems to work whith the co culturing, hope it will do also whith my new larvae.
To Peter from Belgium, what do you do to find rotifers here?
Oyvind

 

[Dman]

As ammonia binders are harder to come by over there, then you have to match up the pH's. A friend of mine in Brazil has a hard time getting it as well but does 95% water changes instead, little risk of increasing the ammonia toxicity that way.

 

[oyvind]

Lowered the pH from 8,0 to 7,5, still dying, hard to watch now that they start to got their first white stripe, the good news is that the 2 days old are eating..