They're both so adorable and look wonderful. I'm sorry to hear about Albert and I hope he'll heal up quickly. I'm also sorry to hear that they may both have runny stools.

Both Alani and Blaze also have very sensitive tummies and ever since I've had them they usually have diarrhea or loose stools with most foods that I've fed them. I've been feeding them Chicken Soup For The Cat Lovers Soul Light dry formula which has a lot of fiber in it and it does seem to help them. They do need more moisture in their diet but everything that I've tried causes them to have more loose stools.

I read this about Manx cats and here's a recipe for loose stool problems:
Many Manx cats and kittens tend to suffer from soft, semi-liquid, smelly stool which their owners have repeatedly linked to canned food and even quality dry food. These cats and kittens reportedly have to use their litter box up to five times a day, some time after they had some commercial food. This problem can affect kittens' weight and growth rate. Canned and dry food may also cause flatulence in Manx cats, as some owners report. This problem can be very frustrating for both cats and their owners, as a result some owners choose to keep their Manx cats and even kittens outside when they are not able to produce hard stool, thus exposing them to cold weather and a risk of predators. The following home-cooked diet has been effectively proven to produce regular, hard, normal stool without any unpleasant smell. Feed your Manx (or any other breed with a soft / semi-liquid stool problem) a mix of home-cooked poultry (turkey, chicken or duck) or fish with little amounts of cooked white rice. A few finely chopped grains of white rice added to each meal are enough to prevent the 'poopy butt' syndrome the Manxes are known for. You can adjust how much freshly cooked broth can be added to this wet food (most cats enjoy drinking fresh, low-fat, non-concentrated broth). Both poultry and fish should be fed to a Manx on a daily basis to provide necessary nutrients. The exact ratio is 2 Tsp. of cooked and chopped fish or poultry to 1/3 teaspoon of cooked, finely chopped white rice. Depending on steak thickness, cook fish for 30-40 minutes, turkey or chicken for 60-90 minutes. Once the broth starts boiling, let it simmer under a lid for the time indicated. Never add any spices or onions to the poultry or fish when cooking, just water and a tiny bit of salt. Cooked poultry can be safely stored in the broth in the refrigerator for 2-3 days, the best storage time for fish is 24 hours. Rice can be cooked in advance and kept in the fridge for up to 5 days. All food should be at room temperature when it is fed to cats, never hot or directly from the fridge. The home-made rice-added diet tends to stabilize stomach problems almost immediately, with permanent results after 4-5 days (flatulence and smelly, drippy stool are eliminated). If a Manx cat gets its home-cooked meals 3-4 times a day, 1 Tsp. of premuim dry cat food can safely be fed at bedtime, this amount should not affect its digestion or stool quality.

I may try something similar for Alani & Blaze. I hope you'll also be able to find something that'll work for your two as well.