Why won't my firemouth grow?

[Sidman24]

I purchased a firemouth at least 3 months ago and she has yet to gain any size! I purchased a second firemouth just about a month ago and he has doubled in size! How come my first one just doesn't seem to get any bigger? Is it normal?

 

[Sidman24]

By the way they are both juveniles

 

[fuzzlebug]

Size of tank? Tank mates?
What's it being feed on? But also its not uncommon for females to slow down in growth when a male is on the scene, the use more energy to produce eggs.

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