Why have my guppies died?

Question

We got 6 male guppies and kept them for just over a week and they were all fine so we added 2 platies, 2 young bala sharks (i know these grow large) and 5 neon tetra.3 days later they were all fine so we added 3 female guppies, 1 more male, 2 balloon mollies and a male and female black molly and not planning to buy anymore at all.

But since then about 5 of our huppies have died and its really sad. They start swimming upside down and fight hard to stay up top. Also one of the platies fin was bit off and then she died.

I dont know why?? The male black molly is the only fish i have seen that seems aggressive, he chases all species and also one of our alive guppies has has most of his tail nipped off??? :(

from reserach i think i must add more female black mollies to calm him down, but am very scared of adding more fish because of stress and more deaths.

help

Answer 1

Have you cycled your tank? Sounds like ammonia poisoning!! Remove the nippers and do a water change, watch the ammonia levels and any time they get high, change the water.

Answer 2

You would need at least a 50 gallon tank or larger to house that many fish to start with.  Also adding that many fish that quickly would cause the ammonia levels to skyrocket and I'm not even sure if your tank was cycled before you started adding all these fish.  

My guess is you have extreme ammonia levels in your tank and it's also probably hugely overstocked.

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Answer 3

guppies are very unstable fishes, so, anything would kill them

Answer 4

Well, you added a lot of fish very quickly. You did not include the size of your tank, but I imagine you have too many fish in a small tank. Fish give off ammonia in their f***s. When you have a new tank, and add the first fish, the ammonia goes into the water and stays there. After a little while, a beneficial bacteria grows to eat the ammonia and turn it into nitrite, which is also toxic to fish. Then after another period of time, a second bacteria grows to eat that nitrite and turn it into nitrate, which is tolerable for fish and removed with water changes. This whole process takes about 6 weeks. Adding too many fish at once, with no bacteria to eat that ammonia, causes the fish to literally die in their own poison. Get some test strips and check on the ammonia levels. Do some small water changes and use a conditioner to eliminate the chlorine in the water you are adding. You should have 1 inch of fish, per gallon of water, on average, to have a healthy tank.

Answer 5

1) you are probaly very overstocked

2) you added too many fish too soon, the most you can add is up too 5 per week.

3) Guppies are usally very hardy (mine survived an uncycled tank and a bout of ich) and still survived. You want to test the Nitrate, Nitrite, Ammonia, and P.H. levels. Espicially since you put in a bunch of new fish.

A good way to stop levels from rising is to buy a few live plants since you probaly already have a light. My personal fav is the java fern, it looks goods, grows on anythings, doesn't need any special treatment and can survive in low light. PLus it spores, and only grows to about 8 inches.