Great, thanks!  Big relief there!

I've had cloudy (very dense) water for at least 3 days. prior to the cloudiness we lost 3 neon tetras. As soon as we saw them we scooped them out. I wasn't sure if them being in there dead was the issue or me possibly overfeeding them. it is a 55 gallon tank with 8 neon tetras, 2 pleomsuscuas (?) 3 mickey mouse fish & 2 aqua frogs & 3 snails. My readings were that the water was very acidic & my nitrate & nitrites were in the dangerous range. I went to the pet store & they gave me stuff for acidity & nitrites & that didn't help. 24 hrs later went back to the store & they said my amonia was high & they gave me another product to use & told me to do another 25% water change. They said it should help within 24 hours...well it hasn't & I'm not sure if I should dump all the water except like an inch on the bottom. we replaced the carbon filters & tomorrow I will take apart aquarium & clean everything out very well with plain tap water. Is there anything else you recommend? what should I do with the fish while I clean the tank already their stress level has gotten high over the course of the day & the cloudiness is still bad. Thanks

As soul said, don't dump all the water. Sounds like your filter bacteria have died for some reason and you've had a bacterial bloom inside the tank. Have you added anything to the tank that may have killed your filter - medication or added tap water without dechlorinator or washed your filter in tap water?

I would do a 50% water change first off and then change 10% of the water each day until the nitrite reads as zero at which stage your filter will be fully colonised again. This could take a couple of weeks.

Good luck.