[dangerousflower]

just last night i bought a lyretail guppy for my cobra guppy to hang out with. the cobra was very docile and curious of others and wanted nothing more than to explore the whole tank.
for the first few hours of introducing the lyretail, the cobra guppy seemed curious and then left him alone. but in the morning, he went haywire and began to antagonize the new guy by trying to nap at his fins, i think i even saw him trying to butt into him, but i'm not entirely sure.
anyways, i'm not entirely sure what to do. i put the bully in a pitcher of water because i have no other place to put him.
ive heard guppies need to be in groups, does this mean i should probably introduce more guppies or perhaps just take the new guy back?
(btw my tank is a 20 gallon housing 5 other glowlight tetras. its got two small amazon swords, 4 anacharis stems and 2 water wistrias)

 

[Romad]

Sounds like male aggression to me You should up the schoold to at least 5 or 6 assuming that you have some good filtration on that tank.

If you decide to get females, you should have 3 females for each male. But unless you want a bunch of fry, stick to males.

You might want to throw some silk plants in the tank for escape areas in the meantime.

 

[RackinRocky]

All fish are individuals. He may just be naturally aggressive, and you'll have to take him back. On the other hand, if you get more guppies, he may stop being aggressive. They are happiest when there are at least several, and I think sometimes not having enough of the same species will make certain fish become aggressive out of frustration. In any case, keep a close eye on them until you can take him back or get more, because he might cause real harm to your lyretail. And remember, the cobra was there first, and sometimes that can make them territorial as well.