Red Tiny Zebra Danios?

i have 7 danios in my 15 gallon tank . I have mentioned earlier in my previous post. I am very new to fishkeeping. So when i bought them home , i saw 3 out of 7 are too tiny ..they dont get harrased or bullied but they are so small ...like 1/3 rd of the big danios. Its been a week havent seen any growth so far. Will they grow?
or thats it?

 

I doubt that they will grow any more. Danios are one of the few small fish that you really have to worry about stunted growth. They are so active that such a large group should be in a 30+ gallon

 

My lfs said m that they are just small they will grow like adults within few weeks.

Thanks for the reply

 

They should grow, you've only had them a week.
Long term they'll need a bigger tank.