Ruby leus have all white fur and red eyes, but when paired to an albino their joeys will all be standard grey (and triple 100% hets) because they do not have the gene for albino. Instead, a ruby leu is both creamino and leucistic.
You might be tempted to pair a creamino to a leucistic in hopes of ruby leu joeys, and will be disappointed to have all standard grey babies.
A ruby leu takes a bit of know-how to breed.
Pairings that produce ruby leu joeys
For the cheaters, you can pair a ruby leu to a ruby leu and all of your joeys will be ruby leus. But be warned, this violates the ancient glider taboo against breeding “color to color,” so prepare for the occasional side-eye from the veteran glider gods if taking this path.
A ruby leu to a leucistic with creamino het will have about half of their joeys come out as ruby leus.
A ruby leu mated to a creamino with leu het will have about half of their joeys come out as ruby leus.
A creamino with leu het mated to a leucistic with creamino het will have about a quarter of their offspring come out as ruby leus.
A ruby leu mated to a standard grey with both creamino het and leucistic het will have about a quarter of their joeys come out as ruby leus.
A standard with both creamino het and leu het mated to a standard with both creamino het and leu het will have about 1/16 of their joeys come out as ruby leus.
Value and Variety
If aiming for highest value, pairing two ruby leus together will net the most ruby leu offspring, but you may quickly saturate your local market’s demand. If neither this nor the community taboo is a deterrent for your situation, and you have the money to invest in two ruby leu parents, this will be the highest return on investment. Second highest value would be a ruby leu mated to a creamino with leu het, which would give only ruby leu and creamino with leu het joeys.
For the best variety of valuable joeys, I would recommend a ruby leu mated to a standard with both hets. This pairing can be expected to produce an equal number of ruby leus, creaminos with leu het, leucistic with creamino het, and standard double hets. This positions you to be a valuable source for anyone seeking to set up a breeding pair to produce ruby leus. It also gives you a variety of joeys to meet a wider variety of inquiries if your local demand is low. This option is a good balance between initial investment and return on investment, as only one parent will be pricey, while 3 out of 4 joeys will be higher value. This is the pairing I would make if setting this up for myself.