Hi all... hey, I just purchased a 5 gallon aquarium (hex shape, biowheel filtration) and I actually... believe it or not... also purchased freshwater that I could "just add the fish" into after water came to temperature (my kid wanted fish that day... hard to dissapoint little guy so this seemed like a good fix).

Anyway, washed the gravel many times, put in water, and when aquarium was at 72F ( about 10 hrs later) I added 5 guppies.

All was great for 1.5 days (crystal clear water) then water got slightly cloudy and 1 fish died. Then I woke up this morning... water more cloudy and another fish dead.

The freshwater that I purchased was in good containers, has real good reputation.. so I am asumming it has to be something I am doing.. Any suggestions/advice? Thanks in advance!!

Whenever I have fish I use natural pebbles without the dye because I had the same problem.
Also you need to have all the filter stuff. I even had to get one of the air bubble makers
You might want to get some snails to keep the glass clean too.

There is a thing called new tank syndrom... basically it takes time for the tank to get into a cycle.. the cloudy water could have been that you had a nitrate spike and thus all the fish died... this is very common but for buying water and just adding fish nope!! You need the tank to filter itself for a minimum of 3 to 5 days. It's a good thing that you washed the rocks... but to fix it do a water change do a good 50% water change... add new water get the water tested and when its good... get some little fishies... have fun!!