How fast Clown Loaches grow?

I have a 125g planted loach tank. I have 6 clowns, 8 yrs old 4-6 inches. 2 are much bigger than the rest and are very fat. 4 of mine were housed in a 55g hex tank for about 7 years before I adopted them from a family member. They have been kept in great conditions with a varried diet (always including some frozen or live foods). Currently I perform 40 gallon w/c every 4 days. Mine have grown very slowly in length, but all have grown thicker. They are my main residents. I have nerver been a heavy feeder because I think the high protein in fish foods is one of the biggest factors in nitrate and phosphate production. I actually fast my fish on Wednesdays. If you power feed they WILL grow faster. Just keep up with your w/c's........

that picture is awesome!
 
I get pics for you ;) All less then 2 years old and between 6-4"

6?i dont cant see it...more like 4 if u ask me(unless my monitor is spoilt)

This is a under 2 years old clown, still under 6 inches.

DSC00075.jpg
 
And here my loaches.
I've had them 2,5 months, they haven't frown much. They are about 7 cm (3 inches)

clown+barbus.jpg
 
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