Can someone teach me how to raise guppy?

[lilfishie]

iv kept guppies with goldfish before and they were fine

 

[novamadcars]

wow guppys are tropical fish and sorry 2 say but thay need a heater
i do actully breed guppys easyist fish 2 bread along side the molly

 

[bubble_gal]

I juz bought my guppies last 3 days~
But one 3 of the females i bought dies.
i really dunno why~
Is it the water?? The weather?? or other things else??
They dies one by one~~ n one day by one day~ How come??
Can some one plz teach me??

P/S: Those deads all are small in sizes....