I think I found out why one fish died

[freshwaterfishlover]

In my 29 Gallon I had one fish die this week and another you can tell is going to go sick soon.

I did all test. Amonia, Nitrate, Nitrite. The last test I did was PH. The PH is usually at 7.2, this time the test showed 6.8 Low. All my test are drops. I think I am going to do a water change NOW.

All my fish except my Swordtail fish do not seem to get effected by anything in my tank. Almost all my fish have not died except my Swordtails. I replaced like 3 Swordtails in 3 1/2 months. Anyone Know why?

[Lady Hobbs]

It was a drop but really not all that much. The pH is harmful to fish if it changes more than .5 in 24 hours.....or so it's written. I can't see as yours did a dramatic drop. Have you tested the water right from the tap before adding to your tank?

[freshwaterfishlover]

I was meaning all the test are drop/liquid tests. I did a water change and PH is back to around 7.2-7.5. I still think the second fish thats acting a slight slight diffrent may still die. I have to wait and see.

[Severus]

What were all your other readings? (nitrite,ammonia,nitrate)