[dwalstad]

Took a couple pictures this morning of one of my guppy tanks. No filter, no aerator, infrequent water changes. Plants are all in pots. Light scattering of STS clay gravel on the glass bottom. The new tank system I started a year ago is working great. Guppies in tank are older adults that I'll use for breeding and my experiments.
I finished one experiment to monitor male guppy fertility with ageing. (Results Attached).
Next week, I'll repeat the experiment with a new group of 9-month-old male guppies and and a new group of young virgins. Photo shows a purple/blue male, one of the new 9-month-old males to be tested. Hope that these new males do a better job at siring than the first group!

 

[Bert H]

Interesting Diana. I have been a guppy fan for many many years. I've always liked the half black variety...I'll recount a story...

Years ago, and I mean something like 15+ years ago, I was in a Petco here locally. There was a tank that had 6 or 7 half black guppies in it. There was no price on the tank. I asked an employee how much they were. The employee replied by saying someone had brought them in to the store for some reason, and if I wanted them, I was free to have them, no cost. I took them.
I have two tanks....a 50 breeder and an old 50 Oceanic which are full of the offspring of these guppies from years back. They have bred true as half blacks all these years. I pretty much leave them alone. The males have red, red/yellow, or red/spotted tails. The females are mostly just half black with occasional splashes of blue or red on the tails.
I love the fact that they have bred true (half black) for all these years. I had bought half blacks in the past and they all had mixed offspring.