Mixing Fluval Shrimp substrate?

Difference in size and settling issues?
 
It may have an effect on how the substrate is designed to function.
 
+1^

If you have to mix, I would only mix it with the other fluval substrates like the flora substrate.
 
I've mixed substrate sizes for years without a problem. Sand mixed with gravel seems to work well with Cory catfish. Just be careful when you vacuum the bottom. I also mix a special plant substrate made of different sizes with no harmful chemicals in it that holds the nutrients and grows a thick root base. Just my 2 cents.
 
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