Hi Misty,
You will find this happen with most species, as there always seem to be a few that get left behind.. despite having the same conditions and food.
Invariably you have to "grade" your fish into sizes and put them in seperate tanks (which is not always possible).. to allow the slower maturing ones to catch up.
It's a little bit heartless... but if you pick out the best of the bunch and cull the runts, you will finish up with a better strain of fish of more equal quality and size.
You also have to look at the big picture and ask yourself how many you are able to keep... or sell.. as the case may be.... and at what regularity.
The Anabantoids will spawn whenever conditions are right and they are in breeding condition, and often lay thousands of eggs.. which you can never hope to save all of, so for my money, selection of the best and feed the rest to your other fish is always a good policy.
It can be a harsh decision at time, but one we all have to face.