Selective breeding project Sabah, Malaysia

We bought a few guppies.
Now we're keeping receipts.

Sabah Guppy is our attempt to document a home breeding project properly from the beginning. G0 starts with two separate groups, Tank 1 and Tank 2. From here we record the fish, the pairings, the fry and whatever traits keep showing up.

Could this eventually become a guppy business? Maybe. Could we become millionaires selling tiny fish? We have the domain now, so clearly things are getting serious.

G0-T1-M1, the first recorded male guppy in the Sabah Guppy project
Historical record · deceased 22 Sep 2026 G0-T1-M1
Where this started

Two tanks. Eight fish. This is where G0 starts.

G0 is our foundation generation, but it is not one mixed group. Tank 1 is G0-T1 and Tank 2 is G0-T2. Both groups started with one male and three females, and we keep those IDs separate so we can trace where future fry came from. G0-T1-M1 died suddenly on 22 September 2026 with no unusual behaviour or visible symptoms beforehand; the cause is unknown and Tank 1 now needs a replacement male.

We do not have confirmed pedigree records for these fish, so we are not filling the site with made-up strain names. We record what we can see, keep the photos and let the next generations tell us more.

On 3 October, a Tank 2 female died. Based on a photo comparison, we have provisionally identified her as G0-T2-F3. G0-T2-M1 was also reported dead, though we do not yet have his exact death date. The causes are unknown. Another female was found dead on 5 October and provisionally identified as G0-T2-F2 from her tail markings. The cause is unknown. These fish remain in the record. G0-T2-F1 is now the only original Tank 2 adult still recorded alive; fry were previously observed in this tank.

Generation zero

The fish that started it

Recorded 21 September 2026 · Tank 1 + Tank 2

Loading the fish records…

Breeding log

What happened in both tanks.

17 September – 5 October 2026

  1. The first four fish went into Tank 1.

    Tank 1 began with one male and three adult females. Their earlier breeding history was unknown, so from the start we knew the first fry might not tell us much about paternity.

  2. Two days later, fry appeared.

    We spotted the first fry only two days after stocking the tank. Because the females were already adults when purchased, these early fry cannot be confidently assigned to G0-T1-M1.

  3. G0-T1-M1 was found dead.

    There had been no obvious change in behaviour and no visible symptoms beforehand. The cause is recorded as unknown, and his record stays in the project because he was part of the original Tank 1 group.

  4. We replaced him with a gold-type male.

    Instead of buying another similar fish, we chose a yellow-gold male with a bright yellow-orange tail and recorded him as G0-T1-M2. Tank 1 now has a different direction to explore, and we will let the offspring show us what the cross can actually produce.

  5. Tank 2 produced its first observed fry.

    We spotted fry in Tank 2 on the morning of 28 September. The exact birth date, fry count and mother are not yet known. Since the females were already adults when purchased, parentage remains unconfirmed.

  6. A Tank 2 female died.

    We compared her photo with the original records and believe she was G0-T2-F3. The identification is provisional. We do not know the cause of death.

  7. G0-T2-M1 was also reported dead.

    We have not confirmed his exact date of death or its cause. His original photo and record remain here as part of Tank 2's history.

  8. Another Tank 2 female was found dead.

    Her orange and pale tail sections, dark tail-base patch and black rays most closely match G0-T2-F2. This identification remains provisional, and the cause of death is unknown. G0-T2-F1 is the only original Tank 2 adult still recorded alive.

    Deceased Tank 2 guppy found on 5 October 2026, with an orange and pale fan tail and black rays
    Mortality reference photo · 5 October 2026. Identification as G0-T2-F2 is provisional.

The experiment

So what are we actually selecting for?

01

Colour we want to look at twice

Red and orange are already showing in G0. If purple turns up one day, nobody here is going to complain.

02

Better tails

Shape, spread, symmetry and colour coverage matter. A nice body with a disappointing tail is still a disappointing guppy.

03

Healthy fish first

Colour is useless if the line is weak. We want active fish that grow well, reproduce reliably and hold their form.

04

Consistency over generations

One beautiful accident is nice. A line that produces the trait again and again is where breeding gets interesting.

How we keep track

Every ID tells us which generation, tank and fish we are looking at.

G0-T1-F2
G0 generation T1 tank F2 female #2

As the project grows, we will add pairings, birth dates, fry counts, selection notes and photographs. The tank code matters because G0-T1 and G0-T2 are separate starting groups. Several generations from now, we should still be able to trace a fish back to the group it came from.

We also plan to keep only a small number of breeders from each generation. The rest may eventually become sale stock. That keeps the project manageable and gives us a very convenient excuse to build a shop later.

The long game

G0 is supposed to look ordinary.

NowG0Foundation fish
NextG1First surprises
LaterG3Patterns emerge
GoalG10A line of our own?

We use G for breeding generations so it does not get confused with F in fish IDs, where F means female. There is no guarantee the fish get prettier every generation. That is exactly why we're taking photos.

Future bad financial decisions

Yes, we might sell guppies.

If the project produces fish we're happy to put our name on, this site will eventually have available stock. Until then, we're breeding, selecting and documenting.

Shop: not yet