Platinum Barb bully
 

I think I put this thread in the wrong place the first time, so hopefully this is the right place to ask this. I haven't had a fish tank in a while, but I decided to get one again recently. I went to the pet store and the Platinum Barb's stood out to me because they seemed every active and playful. So I bought three of them and an algae eater. It was immediately evident that one particular barb was highly aggressive towards the other two barbs. I thought this was fine at first, that they were just playing, but he seems so aggressive. The two calmer barbs will just be chilling at the bottom of the tank or calmly swimming along, and the aggressive one will just start chasing it all around the tank, nipping at the other fish. I haven't noticed any physical damage to the two barbs so far, but should I be worried about the aggressive one? Is he stressing out the other two fish or is it all in fun? Any insight on this would be great, thanks!

Typically barbs need to be in a group to spread out aggression, ensuring that no one particular individual is signaled out for constant harrasment. What size is your tank??

The tank is um... size 14, it says, which I think is 14 or 15 gallons? The pet shop said as long as I get three or more they would be fine, so I just got the three and plan to add more slowly.

I'm going to have to google Platinum barbs; I have no idea on their adult size.
What species algae eater??

I think they only grow to be about 3" long. Right now they're about 1.5 or 2"
The algae eater is totally fine, they never mess with him. He's about the same size as they are but they ignore him and he ignores them.

Just curious as to the type to know what his full adult size is going to be.

Oh sorry, I think it's a pleco

Hummm...different plecos grow to different sizes. The common pleco reaches 18", the bristlenose only reaches 4 to 6. I'm still not finding platinum barb info on google. Definitive info anyway.

Sorry about the delay in reply, I had to go out. They're actually just a color-type of Tiger Barbs I believe. And yes, the algae eater is a bristlenose I'm pretty sure.
What would you suggest about the Barbs? Do I need to add more ASAP to make a bigger school or is it that my tank is too small? I told the pet store my tank size before I bought them and they didn't say anything about it.

Those darn pet stores! Tiger barbs can reach three inches full grown, really do need to kept in a group of six, and from everything I've read they should be in a 55gl. The require lots of room and are very active. I wonder if you can exchange them for something more appropriate for your size tank?