I am new to the forums and have had a thought about my little "runt" in my loach aquarium. I currently have 5 loaches (4 clown loaches and a yoyo loach) in a 30g aquarium. I do water changes weekly, has a HOB biowheel filter, and a bubbler. Tons of hiding spots. AND yes, I realize it's a small tank and will soon be converted to grow out tank for other fish while I am getting my 55g cycled as I write.
My oldest clown loach, who is going on a year, is about 5-6 inches. I purchased 2 new ones about 5 months ago then another about 1 month ago. It seems that the smallest one, aka the runt, does not seem to be growing...at all. I notice grow in the three of them except the little guy. This worries me.

I feed them a consistent rotating diet of algae thins, brine shrimp and blanched zucchini/cucumber. The runt eats great and from what I have read, sometimes the alpha loach doesn't let the little guys eat but this is NOT the case in my aquarium. Everyone eats happily. Just the little guy hasn't grown and it worries me because I have read that most clown loaches grow a lot in their first year, which I have experienced with my other ones.
I could only guess it's a parasite(?) but not really sure. I have included pictures in this post and would like to hear as much feedback. Thank you!

Above right


he's the one on the top, depth is a little weird on this one.

to the left
