I never had a problem with tiger nuts and worked pretty well for me. In addition I like to add a small bit off sweetcorn pellets, mixed with a bit off trout pellets in a pva netting as catfish is not a problem.
Another method that I like to use is to take a very small paste spring, take a large hard floatie, dip it in pepper sauce tabasco, pull the spring slightly apart and place it inside the spring. This must be done after installing the small shafted rubber elastic. Then I use brown bread for a baste mix it with, pronutro, horlicks etc and makes a high quality paste. This I paste around the floatie onto the spring. prick it with a tooth pick so the tabasco in the floatie bleeds out while in the water. The spring kit is provided by western accessories.
Then I attach this to the hook by threading the braid through the little hole in the elastic with the needle, before slipping the braid over the point off the hook. This bait is very light due to the floatie inside and will sit very lightly on the bottom and on top off the silt if not to deep. I then attach the hook link to the stiff boom as in a combi rig. You can make the brown bread base a high protein but please do not do this if you do not want to go to some trouble to ensure a proper bait.
Or you can take a boilie base microwave it for 1-2 minutes depending on the buoyancy you want, instead of cooking, approx 8mm in size and place this inside the spring.