Seahorses, H. erectus are doing well but is 5 okay!

I started a seahorse tank about a month ago and all five look great.
My question is that I have an odd number-5 and wonder if this will be a problem. I know that at least two are female but not sure on the fifth one-it was an ad on. I purchased two pair and the fifth was to cover an overpayment on my part.

 

Shouldn't be a problem.

 

how come they didnt just give you your money back?

 

I suggested another horse rather than a refund. However, now that the pairs are comfortable (two pairs) I was worried about the odd man out.

 

i would suggest that they would possibly fight or more likely that that one stray bachelor will keep the 2 pairs tight. or if your tank can handle it you could always get him a partner