No, they don't. The only things that would cause "floaty" issues are the following: 1. Genetics. 2. Floating foods. Some get "floaty" despite the reduced starch content so this comes down to air being ingested even though most goldfish tend to spit the air as they chew. 3. Food expansion. Most pellets expand more than the normal size. Presoaking has always been suggested but this also degrades its nutritional value. Best incorporate the pellets in gel foods recipes. 4. High starch content. Lots of fish foods contain the starch based ingredients including brewer's dried yeast, soybean meal, etc. Those are responsible for the floaty issues. When the bacteria lining the digestive system start to digest starch, they also produce gas which in the process gets trapped inside the GI tract (GI=gastrointestinal). This is why most gel foods have acidophilus added for this reason.
I prefer to use natural foods, homemade gel foods and sinking pellets with low starch content particularly Hikari Lionhead although I also use floating pellets with no issues as long as fed in small multiple meals. You could also buy Mazuri gel foods. 5M70 is recommended for young goldies.