I had 4 male guppies in a 26 ltr tank ( i know it is small but was panic buy to save death from beasts in other tank that turned on them one day)
All been fine to date.........
ammonia 0
nitrite 0
pH 7.6
nitrate 4 test results from this morn when all seemed fine.
Went out, came back 2 hours later one dead! Others active. Did 20%
water change
I now have my fave( Billy) lying on the bottom looking as if he is trying to swim but can't get up!!
No white spots, no sign of damage to him......
Any ideas? What could cause such a sudden death and ill health in another?
Other 2 still playing in bubbles!! If i can help Billy it would be great