I am wondering about gravel size and such bc this weekend I am changing the substrate media in my tank. Really I think I just need some expert advice explaining some of the differences to me. I have looked at every gravel at all the local lfs's with no luck. Not even big al's!
I have been told several times that my gravel is somewhat abbrasive to the barbels of the loaches. I have used this gravel for close to 2 yrs with my alpha loach and I havn't ever noticed any injuries.
In my other tank, the gravel is roughly the same size and texture. I did notice a torn barbel on one of my corys for the first time. This cory has lived on this gravel for more than two years and this is the first occasion that I have noticed it.

The red gravel in my tank is roughly about this size and texture. I was wondering how this gravel is any less abbrasive on the barbels? I guess it is slightly more rounded in loachmom's tank but near the same size.
loachmoms gravel

what i really want is some gravel like these two pictures. i couldn't find any this texture anywhere local.
ashleighs gravel

vancemans gravel

which would you consider a better texture for loaches from these pictures?
Is this smaller gravel in curtis's tank a better size. I find that my loaches don't seem to mind the gravel size. they pickup the pieces and dig alot. I would love to make life easier for them with this smaller gravel.
Most of the local gravel around here is just like the red gravel I have but painted different colors.
Right now the combo is going to look something like these pics below but with some additional gravel like curtis's on top spread randomely.


I am just interested to hear some opinions on this matter. Does anyone think that I should just add the sand and the larger rocks and see how the loaches react to it before I add more gravel.
I also think that adding the smaller gravel on top of the sand may make things a bit difficult to separate once I upgrade tanks.