New male guppy with bitten tail

[swimmers8]

We bought 6 cardinals, 4 minnows and 4 orange danios. We had them for about 6 months then decided to add a few more fish. We chose 3 guppies (1m and 2 f) and 3 platys. After a few days I noticed that the male guppies tail has been bitten and it having difficulty swimming horizontal. Which of the other fish would have attached the guppy? Do I need to isolate this fish whilst its tail regrows (do they re grow and how long would that take?) hope someone can help. Thanks.

 

[Logic]

what is your tanks ize and parameters

 

[snork6]

How long has the tank been running? The danios might be the culprit if your tank is too small for them

 

[swimmers8]

what is your tanks ize and parameters

We have a 54l tank.

 

[swimmers8]

How long has the tank been running? The danios might be the culprit if your tank is too small for them

The orange danios are tetra sized. This morning I found a cardinal and the guppy dead so I think I've found the reason. Are guppies or cardinals territorial? I want to get reolacements. What's your advice? Thanks.

 

[snork6]

Are guppies or cardinals territorial? I want to get reolacements. What's your advice? Thanks.

Guppies are mostly non-aggressive fish. That's why they are called community fish. but every now and then you can get an aggressive one. And I have heard of cardinals being aggressive but very rarely. Most likely the reason your fish are fighting is because your tank is overstocked. 20 fish in a 15 gallon tank is just too many.

 

[swimmers8]

Guppies are mostly non-aggressive fish. That's why they are called community fish. but every now and then you can get an aggressive one. And I have heard of cardinals being aggressive but very rarely. Most likely the reason your fish are fighting is because your tank is overstocked. 20 fish in a 15 gallon tank is just too many.

Thank you. This is helpful.

 

[snork6]

What's your advice?

As for my advise, I recommend just trying to get your money back and not attempting to add more fish

 

[swimmers8]

As for my advise, I recommend just trying to get your money back and not attempting to add more fish

One further question - found two more cardinals dead yesterday and today. We bought a new air bubble feature. Could too much air in the tank be the reason. The cardinals have been fine for 6 months since we bought then, the suddenly 3 cardinals haved died. From your experience, have you seen that? Thanks

 

[snork6]

One further question - found two more cardinals dead yesterday and today. We bought a new air bubble feature. Could too much air in the tank be the reason.

These do very minimal to improve tank oxygen and are basicly a decoration/marketing scam so no that wouldn't be the problem.

As for why your fish died, I would need to know the parameters of your water, that usually is the culprit. You can buy your own testing kit which is recommended or take a sample of your water to your local fish store to have it tested. DO NOT ACCEPT "YOUR WATER IS FINE" AS AN ANSWER FROM THE PET STORE. Ask them to give you the actual numbers of
Nitrate-
Hardness-
pH-
Ammonia -
Nitrite -