so ive had these fish for a couple yrs now. im not sure how old they are. i got them from a buddy of mine. so over the last two yrs ive lost 6 of the 7 blood fin tetras to some weird disease i think. they had bent spines. so there is one left of this little guy. also i have one black skirt tetra left out of the 4. should i get them new buddies to hangout with or wait for them to pass? i cant decide which would be a better option.