"different aptitude" is correct and usable in written English.
It is used to refer to special talents or gifts that an individual has in certain areas. For example, "He has a different aptitude for mathematics than he does for writing."
Individuals also differ, having different aptitudes, interests and abilities.
"But different people have different aptitudes and they know different tricks… it turned out their combined efforts can be much quicker".
The story of penicillin shows very clearly how different aptitudes and temperaments can supplement each other in the advance of science.
Just as taller students can more readily reach higher objects than shorter ones, it is not just a matter of more and better instruction, but one of different aptitudes and different instructional needs.
How do you define that shifting period of transitions between the ages of 8 and 10, or 7 and 10, when children read at very different rates, with different aptitudes and for different reasons?
Keystone Education, which offers specialist education tailored to different aptitudes in several states, claims that 80% of its graduates keep on the right side of the law for at least a year after they have left, whereas just 20% or so from the state's special schools do.
When you look at the variety of public schools that have worked well in the U.S. — in cities big and small, and in suburban and rural areas — you wonder why anyone thought it was a good idea to throw a stultifying blanket of standardization over the education of millions of kids of different aptitudes, interests and levels of maturity.
From eternity souls have different qualities or potentialities (different "aptitudes").
Thermoplastics have different aptitudes for welding and joining.
However, the presence of young farmers raises the percentage of policy consumption, but within the group of young farmers different aptitudes stand out.
