Help Please. Fry Keep Dying. No Explanation

I have two sets of fry, born a couple days after each other that keep dying. Currently around 2 weeks old. This gave me a total of approx. 60 fry living in breeder tank.

All was fine the first week and a half. I went away for one night, came back the next day and had about 8 dead fry.
I checked the water parameters and all was fine. Water temperature is where it should be. The water had a 30% change two days prior and they all made it through that. I went ahead and did another 30% water change anyways.
Water changes have been every two days since birth.

The next morning I had 6 more dead fry. By evening another 5 had died. At that point I thought possibly the food was causing them to bloat and get swim bladder. I went ahead and cut the food amount by 2/3.
The next morning 4 more dead and one swimming head pointed down, common of swim bladder. I then cut food completely for 24 hours. This did not help, through out the day I lost more fry. In the past two hours I have watched 3 fry, acting seemingly fine, suddenly start swimming head pointed down and die within 20 minutes.
Over the course of 2.5 days I have dropped from around 60 fry to 26 total

They are eating pulverized flake food. I know many people won't give this to fry but I have never had an issue in the 6 years I have had fry.
Excess food & dead fry are removed daily with turkey baster.
Temperature is being kept at constant 79 degrees.
Water parameters tested daily


Any ideas what could be going on? I am not a fish expert but have raised guppies successfully for 6 years and have never seen anything like this.

As I typed this another fry died.

 

With those numbers of deaths, your clear knowledge of fish keeping, and solid water parameters it's gotta be either a chemical contaminant in the water or something infectious, I'm thinking.
How are the adult fish doing? Particularly the ones that birthed them, if you know which they are.

 

Adult fish are all doing well including the ones that birthed them.

I pulled one from the tank when it looked like it was dying and put it into a small holder with 100% new treated water. For a while it looked as though it wouldn't make it. However I left for about a half hour to pick my kids up from camp, and when I got back it was swimming around just fine.

I have pulled them all from their tank and separated them into Tupperware containers with 100% new water, 2 per container so I can keep an eye on them easier, while I completely scrub down their tank and filter. I will be cycling a new filter bag. I also discarded all plants and will go pick some new ones up for them.

As of right now two are still having problems (they were already having them when I pulled them from the tank). One seems pretty weak, the other it thrashing about trying to get upright. I am optimistic that this one will make it.


Not sure what exactly is wrong but that fish making it tells me something was off in the water. I'm thinking chemical contamination, since the one pulled through.

Is this something that is common? How can it be prevented? I have never come across anything like this.

 

Wait where did you get the fry from?

 

my guppies gave birth to them

 

Thought I had solved the problem. 4 more guppies dead. The one who had pulled though ( as stated in my previous reply ) died as well as three others. Not sure what to do at this point

 

Honestly I don't know what to say but maybe it could be they aren't that strong? Did the mother birth them prematurely or maybe it's their genetics?

Another thought I had was maybe the fry prefer a different water such as preferring soft water. I don't know if this will help whatsoever but I hope the remaining survive.

 

They were birthed from two different females, I doubt very much so that they were premature. Both mama fish were in the breeder tank long before they were due to avoid stress. Its possible one birthed premature, but I doubt both did. And you would think if they were premature they would have had issues right away, not a week and half after birth.

Since my last post all but 5 fry have died. Three are currently on their way out. The two that are still very much alive seem to be going strong, but that's how they all have been, then with in minutes they lose it and start swimming head down or upside down. If I tap the tank, its like they wake up and start swimming fine again for about 30 seconds they start to head bob again. They can play that game all day, if I stop doing it they will die in about 5 minutes

I originally thought swim bladder, then I thought chemical contamination. But neither of those makes sense with their actions. It's literally like they are drifting to sleep and as long as you keep them awake they keep kicking

 

This happened to my Cory fry until I got the feel for it. When I got the feel for when they are hungry/ need a water change many more survived!

 

I have had many many sets of fry live with no problem for several years now. I have had weaker groups where less survived, but I can tell based on their swim patterns and that is just a matter of genetics and how they were birthed.
What is going on with these guys I have no explanation for.

 

I have had many many sets of fry live with no problem for several years now. I have had weaker groups where less survived, but I can tell based on their swim patterns and that is just a matter of genetics and how they were birthed.
What is going on with these guys I have no explanation for.

Ok, explain to me how you are doing water changes. Have you tested the water you put into the fry tank? What is it's readings?