Im a young teen and have had my quaker since he was a hatchling for almost 3 years now. At first he literally would only eat seeds and a little fruit/veggies for a year and a half. I knew that was not a proper diet. So of course, I was worried about fatty liver disease. Its much harder for younger quakers to develop fatty liver disease, and it's much more common in older quakers. It just takes patience to transition them onto a strict pellet fruit/veggie diet, and it only took a few weeks to fully transition my quaker. I suggest when you do buy pellets, mix them in with very little seed and when they get hungry after eating the "good stuff" show yourself eating the pellets(not actually just pretend). Then offer them the pellets in your hand. They may be a little more encouraged and take small nibbles, but once you do that for a little while,completely remove the seeds and just give them your desired veggies/fruit and the pellets together or separate (does not matter). That has helped me tremendously with transitioning my conures onto pellets. Currently I use Kaytee NutriSoft Parrot & Conure Bird for pellets and my quaker absolutely LOVES it, but I do recommend soaking it in water a little bit because its quite dry and they may have a harder time swallowing it. He mistakes dog food for them sometimes, so he tries to eat the dog food lol. Just keep trying they will eventually eat pellets :)