Some help please, fin biting and questions!?

[gmac]

Well things have been going quite well in my tank and everyone is getting along. Had the fish in the tank (fishless cycled 30 gal) for 3 days now:

12 Neon Tetras
2 Black Mollies (1 male, 1 female)
1 Balloon Molly
1 Siamese Fighting Fish
3 Male Guppies

I put the 3 guppies in the day after the rest of them however. Two of the guppies have had chunks taken from their tails, one has had one nibble and the other has had at least three - I think he is the youngest as he is slightly smaller in size but not my much. The largest guppy with no bites swins confidently into the filter output stream constantly without problems, the others do too every now and then... do they like doing this guppies?

I am confused by this as I'm unsure if it would be the Siamese or the Mollies, the Siamese doesn't bother about any of the other fish and has a nice personality from the start. The little guppy has taken to doing his own thing and hiding out in places and being alone although came out for a sprint about today for a while and some food once he saw it - could this be him unsure on his feet around other fish and learning the hard way?

It always seems to happen at night, and the Mollies (especialliy the big male black one) come out as soon as the lights go off - is this normal? They stay in a dark corner till lights are off then it might be them doing this under cover of darkness.

Also can anyone tell me how you sex a neon tetra and of their mating ritual if any? Also ritual for Mollies.

Sorry for all the questions, many thanks!

 

[patryuji]

Male guppies have big colorful tails...bettas tend to dislike other fish with big colorful tails and will "beat up" any of the guppies that get close. It could be other fish but the betta is the most likely culprit.

 

[TankGirl]

It is generally recommended not to keep bettas with any fish that has flowy, showy fins, and that would include guppies. I am sure there are people keeping them together but I think the betta is responsible in your case.

Do you know the gender of your mollies? The balloon molly can interbreed with the blacks so it is better to sex them all and see what you have. More females than males is a good way to go, so any female does not get harrassed to the point of illness. If the mollies are hiding until lights out I would suspect they do not feel comfortable and perhaps the betta is responsible for this as well, keeping them hiding until lights out. It is how fish behave when they are not comfortable, so you may have to provide more cover in the form of fake or real plants, decorations, or rearrange the decorations you have. You also might try keeping the betta in a 5-10gal on his own for a bit and see if the mood of the tank changes.

Don't know how to sex tetras - they are egg scatterers so if you want to breed them it is best to keep them in a tank all on their own, perhaps with marbles in the bottom so the eggs fall down where the fish can't get to them.

Mollies are easy - the males have a modified anal fin that is somewhat cone shaped, not a fan shaped like their female counterparts. The males actually use this fin to inject sperm into the females and the females keep the eggs internally and live fry result, thus the term "livebearer."

Good luck!

Good luck!