Fish poop color changed

[Ruturaj]

I am not sure if this is indicator of anything

My fish's poop used to be brown red color, tank was cycled

Last week I thought my fish had some kind of infection, so added some methlyne blue

Now his poop is all black or white

Didn't change the food. Ph used to be stable at 7.5, is now 8.4

Ammonia 0.25 ppm (not sure because water has slight blueish tint)
Nitrite 0 ppm

 

[Ruturaj]

Seems like methlyne blue did it, fish looks healthy and is eating. Added carbon to filter to remove methlyne blue. pH is back to 7.4 and ammonia is indeed 0 ppm.