Well there is a very simple solution
Corries are larger than otos so it produces more waste.
since there are 2 than it is obvious that the corries produce more
The above information is not true at all and is somewhat inaccurate in most situations. When taking into consideration the larger fish does not produce a higher bio load. The one who has a higher bio load is the bulkier one, the one that eats more, the messier one, and in some situations, but not all the larger one. Even in this situation an oto will easily produce a higher bio load compared to a Pygmy Corydoras, not Becasue it's larger. Because of its eating habits and how bulky it is. So taking into consideration of listing the preferred species of the particular species that you are speaking about would be great
Also, you are aware that Corydoras should ideally be placed in groups of 6+. So a group of 2 wouldn't be sufficient
Otos also should ideally be in larger groups around 3+ so 1 wouodnt do very well
Also. A note about your "blog"
You relise that about 50% of the information is correct and there are multiple spelling errors throughout the website