Why is this happening?

[T3hdarky]

Alright, so when I first started my 15 gallon aquarium it had about 30 or so baby guppies in a breeding net, and about 10 platies (4 pregnant) and 10 guppies (2 pregnant) and two baby crayfish. I had seen a couple of my guppies die and I believe it was the crayfish because I saw it grabbing it and killing it, so I gave my two crayfish away. And I got a Albino corydous, but still after that, one guppy died, i mean the platy are doing fine, why do you think this happended?

Also another question, I have 3 or 4 fat as cab get platys (pregnant) And I'm sure they are, but they've been that way for a week by now, how come they havn't given birth yet?

[ishar]

... I am surprised that is all that is dying in your tank to be honest!

Your tank is very much overstocked. I don't know if you have cycled your tank, or if you know what that means, but if you haven't you are going to have many more deaths on your hands. Read what I am about to post and then come back here and we will help you out ok?

For starters: cycling. In your tank there is a cycle that happens dealing with nitrogen. When the fish excretes wastes and as old food decomposes, these things turn into ammonia. This compound is very harmful to your fish even in small levels. In an uncycled tank this ammonia just accumulates and then everything in the tank would likely die. However a bacteria develops after a few weeks and it consumes the ammonia, converting it into nitrITE. this nitrITE is also quite poisonous to your fish, but just not quite as much. After a few weeks of the bacteria converting ammonia into nitrITE, a new one shows up that converts nitrITE into nitrATE. NitrATE is relatively harmless to your fish and can get to very high levels before it becomes lethal to fish, but not such a high level for invertebrates like shrimp and crayfish.

Your tnak specifically is very overstocked. The general rule of thumb for an aquarium for small community fish like you have is 1" of adult fish/gallon. Guppies are between 1 and 2 inches- we will say 1 here. Platies are the same. So right now you have over 20" of fish in our tank. That is well overstocked. On top of that you have 30 guppy fry that would grow up one day into adults too. As you can see, by taking the smallest value for your fish lengths you are overstocked- this was a very conservative estimate. Being overstocked means that the ammonia levels are going to rise to a point that the bacteria cannot keep up with converting it to nitrite, even after the tank has been cycled and established. Your fish will get poisoned if this is allowed to happen. They are also not going to get enough food to each of them because there are so many, and overfeeding can only make the whole problem much worse.

Unfortunately, I don't think you have much choice. If your tank is cycled already and you just didn't mention it, then that is good, but you will need to return a lot of fish... If you kept maybe 5 male platies and 5 male guppies and your corydora you would be ok. No females as they will produce babies like you wouldn't believe and then your problem is back again. If your tank is not cycled yet, you need to take all of your fish back, and then do some research on how to cycle your tank. Once it is cycled you can slowly add your fish to your tank.

Please ask us any more questions you have. I hope this post helped you out. Let us know what else you need and we will be happy to help.

Welcome to the tank by the way

[T3hdarky]

Yeah, my tank is cycled, and I have another 10 gallon, should I possibly put my guppies or something in there?

-Thanks for your help

[ishar]

hey no worries- that's what I am here for

Ok, I am very glad to hear your tank is cycled. That makes your life a lot easier. What are your water parameters? do you have the standard test kits for ammonia, nitrite and nitrate, and perhaps pH as well? Those numbers would be really helpful.

What is in your ten gallon right now? You could use it to store the other half of your adult population possibly, but you still have more fish than you have room. How many do you have of each gender for your adult guppies and platies? That would help see what is going on as well.

[T3hdarky]

Umm right now, I have about like 6 or 7 female platys and 3 or 4 males. And pretty much the same for the guppys, but I saw another guppy die today and it was my favorite one. Why is it only the adult guppies are dying, and not the baby guppys or the platies? Perhaps a bully in the tank? I'm really worried right now.

at the moment I have nothing in the 10 gallon.

And what did you mean by the water parameters? the tenpature? The tempeture of the water is fine right now.

[Kissyboots]

Parameters are the levels of Nitrate, Nitrite, Ammonia, pH, and whatever else you might test for.
I don't suppose you have a testing kit?
I would strongly recommend getting an API Master Test Kit. Our sponsers "Aquariumguys.com" have a sale on them right now I believe.

[T3hdarky]

oh; hmm I don't think I have one. :/.

But why do you guys think that only the guppies are dying and not the baby ones or the platy or the cory?

[Kissyboots]

I don't know why they're the only ones dying, but I would try to figure it out really quickly!

You can get test strips at Petco or Petsmart but I don't recommend those cuz they aren't very accurate. I would go for the API test kit. Get that somewhere other than a chain store cuz they are way overpriced.

Sorry, can't help you much more unless you can figure out if it's your water (almost always that's the case )

Edit: And, yeah, your tank is way overstocked. Is the 10g cycled?

Edit2: Where are you planning to put all those babies btw? That's a lot of fry and they get as big as mom and dad!

[MadridKid]

i got platies too right now...i have no clue, and the same happens to me with the pregnant junk....i hate it when i get millions of new little fish in my tanks...i feel responsible to keep them alive and make sure their okay in the end...

[Kissyboots]

I don't think guppies live very long. Maybe they're just too old.