help pink tailed trigger needs help

[Aquattro]

Yup. That many carnivores added to a tank at the same time (and that tank is too small for all those fish) is going to cause a lot of toxins to build up. They are all messy feaders and I bet if you test for ammonia, you'll see the reason you're having trouble. Do a good sized water change now to help them out. Then take some back to the store.