Guppy Disease

Guppy fish used to be my favourite but now my interest is water plants especially water lillies.
But one cannot have a pond without fish.
The mosquitoes would take over in no time.
Guppy fish is the only solution.
But over time the fish lose their bright colours and become the wild type.

The wild type is resistant to disease.

 
Just to introduce some colours I bought a batch of bright coloured guppies.
Knowing very well they are incubating guppy disease I introduced them to the stock tank.
I added few of my wild guppy to interbreed.
In no time one by one all the guppies started dying
Not other fish types.
It was evident that the guppy disease was the cause.
I believe it is a virus disease and over time they become resistant.
But unfortunately my fish in the main outdoor tank started dying.
I made sure there was no contact or contamination.
I was puzzled and worried the fish food was the cause.
I need to work on this.
The vendors treat these disease fish before selling.
Within 24 hours they show the signs of disease and start dying.
If you buy a new stock do not introduce them to your main tank.
Observe them in a hospital tank for at least a week.
Treat them if necessary and introduce only the healthy ones.
Ideally the next generation of young fish.
If they are healthy they breed and breed fast.
You have a healthy batch then.

I now think even contaminated fish food carry disease if not guppy disease (viral) but bacterial disease.

Fish do not have a well developed immune system and succumb to diseases especially bacterial.

So keeping the tanks in good healthy condition is a priority.

Every time one introduces new fish this risk is increased or multiplied.