A principal advantage of using extruding machine to make aquafeeds is that it permits sinking and floating diets to be produced on the same equipment.

If some floating feed is generated during the production of sinking feed, the following measures can be took for troubleshooting:

1. Readjust kneading elements to make all the kneading elements arranged to feed reverse;
2. Replace the short twin-screw and kneading element with middle section singe screw and remove the shearlocks;
3. Add a vacuum pump for creation of vacuum at the pressure relief opening;
4. Add density control equipment at discharge outlet;
5. Reduce the rotation speed of the principal machine of extruder.

Generally, configuration 1 is more economic without adding any accessories, but have little effect; configuration 2 has good effect and only needs to replace one section screw, it also was employed on MY165 extruder machinery for producing sinking river crab feed which is more difficult to be manufactured, even so, at given formula the obtained end products delivered good quality with conditioner temperature maintaining above 90 , while the conditioner temperature can only remain about 80 and some floating end products were produced when configuration 2 was not used; configuration 5 is theoretically feasible, but it needs to replace belt disc to control the rotation speed of main machine due to the absence of frequency-transformer on single screw extruder, which is relatively more complicated for application; configuration 3 and configuration 4 are of relatively high cost, and if addition of equipment took account configuration 4 is recommended which provides good performance and easy operation.