Clown loaches not growing

[typicalalex1]

I bought 4 clown loaches about 9 months ago from my LFS. They were about 1.5" at the time and they are still that size. They haven't grown at all in that time.
I bought another 4 a few months later from another fish keeper, they were about 1" bigger and they have probably grown another 0.5" since i got them.

They all appear to be extremely happy. They are constantly swimming about at all levels of the tank, mainly in the middle rather than the bottom which i think is weird. They eat like pigs as well. They all go to the surface when anyone goes near the tank and even start nipping at your fingers if you put them in the tank.

None of them are skinny so i don't think they have skinny disease.

They are in a 100G tank with an FX6 and a 5000 litre wave maker which they love swimming against.
Tank mates are silver dollars, 1 raphael catfish, 1 firemouth and 1 convict.

I do 1 70%-80% water change per week.

They are fed 1/2 times a day on a variety of NLS cichlid pellets, algae tabs, blood worm, mussels and the occasional cucumber and lettuce.

Anyone have any ideas as to why they haven't grown?

 

[Ihsnshaik]

No idea I just know clown loaches grow very slowly. I have 2 loaches at 3" and they barely have grown in two months.

 

[Chillz23]

VERY slow growers.

 

[that_fish_Guy]

you are doing everything just fine. nothing your doing sounds bad. The problem is is that Clown Loaches grow very very slow. That is why very big ones can cost hundreds and small ones are sold for only several dollars. I would say just be patient it is completely normal.

 

[convict360]

I've also heard that bigger loaches may inhibit the others growth, by becoming the alpha; do you have a clear leader among the shoal?

 

[typicalalex1]

I do understand that they grow painfully slow.
Just find it strange that they haven't grown at all in 9 months. The ones i see in my LFS seem bigger.

 

[doviione]

mines grow slow too, normal

 

[FunWow!]

For the most part they do grow slow but small clowns grow fast to about 5-6inches and from there slow down. I've had 2inch clowns grow to 5inch in less then a year and others grow slower. You need to feed a lot. Carnivore and massivore pellets help too. Any of your clowns every have white stringy crap?