as said previously, a heterozygous gene must be carried by both parents to guarantee albino hatchlings. the produced offspring can be represented as followed:
normal = B (dominant gene)
albino = b (recessive gene)
eg.
1.BB x BB (normal x normal)
= BB, BB, BB, BB (100% chance of normal)
2. BB x Bb (normal x normal - one carrying recessive gene)
= BB, Bb, BB, Bb (100% chance normal)
3. Bb x Bb (normal x normal - both carrying recessive gene)
= BB, Bb, Bb, bb (75% chance normal, 25% chance albino)
4. bb x Bb (albino x normal)
= Bb, bb, Bb, bb (50% normal, 50% albino)
5. BB x bb (completely normal x albino)
= Bb, Bb, Bb, Bb (100% normal however all are carriers of the recessive albino gene)
6. bb x bb (albino x albino)
= bb, bb, bb, bb (100% albino)
sorry if i got carried away but hey, you asked how albinos came about!