Medaka's slowly dying
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Hello everybody,
Recently, I have had trouble keeping my Medaka rice fish alive. They seem to die one after another, every couple of days. They don't look ill and eat well before they die. They're in a nice ceramic fish bowl on the floor of my house and did well for a couple of months.
I have two types of water at home:
Number 1: Treated water from my water softener (GH < 3, KH 15–20, pH 8)
Number 2: Untreated tap water (GH > 14, KH 10, pH 7.6)
The third test strip is from the water the fish are in.
I basically only use water number 1 in their bowl, yet the KH and GH are (way) higher in there than in the tap water.
Could the bowl be causing this? And if so, why didn't they start dying much sooner?
All other parameters seem to be okay.
Thanks in advance!