Guppy Tank Dying

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Aquarium Advice Newbie
Feb 14, 2024
United States
Started a 10g guppy tank but I am having some issue as my poor guppies just keep dying one by one. I used filter media from an already established tank to get the cycle going and from there I test the water daily with an API kit until i got the all clear to stock. I started with 12 fish total 2 males and the other 10 were female but unfortunately I am down to just 4 females and I cannot understand why. I have babies in the tank in a mesh breeder box but for some reason they seem to be unaffected by whatever is taking out the adults the couple shrimp i have in the tank also seem unaffected

Tank parameters:
pH = 8.2 (all my tanks have a pH of 8.2 since where i live has alot of calcium)
NH3 = 0ppm
NO2 = 0ppm
NO3 = 20-40pm
Temp = High 70s (F)

Some of the symptoms include:
Flashing against substrate(My longest living male was doing this up until him passing today but otherwise looked and acted fine before getting sick and losing all his color)
Obsessive top of tank swimming
1 female had an odd white growth on her right before she passed but I have not seen it since.
Major loss in color as death approaches typically i will notice weird behavior when checking on the tank before work and usually 9 hours later when I get home that fish has passed
Loss of appetite was not an issue even the fish I thought were acting weird would snap out of whatever trance they were in when food was dropped into the tank.

I have attempted adding aquarium salt to the tank as well as an all in one treatment from lifeguard as I have no idea what could be causing and this medicine was a hail mary and all i could find readily available.

Please be kind but any and all help is much appreciated it
Unfortunately, most Guppies you get from box stores and many pet stores in general are not the strong fish they used to be. Due to the breeding methods necessary to obtain the different colors make the fish genetically very weak. If you are going to get Guppies, you'll want to get them from breeders so you know the genetic lines. ( The same thing has happened to Angelfish. They now are very fragile and a genetic bowl of soup more than pure lines. :( )
As for your fish, there is a strong possibility that yours have internal worms which could explain the loss of color. This is a free link to one of the best books with a diagnostic flow chart that is easy enough for the average hobbyist to use. ( ) I suggest you download it and go through the chart to help you figure out what your fish have. It's free so no reason not to have it as a good reference for the future and your other fish. Be aware that since it is an older book, some of the medications are no longer available or may be now under a different brand name but the key is the diagnosis. Once you know what you are dealing with, we can help you with what medication currently available you should use for treatment. (y)

Hope this helps. (y)(y)
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oh thank you i will take a look at that pdf and see if i can figure it out. Still getting used to this site so I didn't even see the other post
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