Newbie.. please help!!

[Morning32]

So. Here I am looking for hopefully the best advice to keep my fish alive. I'm Ashley. I live in Chicago and I have a 10 tank with only one guppy. I did not know about cycling before I bought 5 fish. I added them and then one by one they died I cried and felt devastated. I added tetra startup (with Bio Spira). However, one guppy is still alive. We have had the tank a little over a week. The guppy however has kind of a black end. It seems as if he has ammonia poisoning? My snail was dead in the tank for 4 days. I thought he was hiding. I am not sure if this has caused the higher levels. I did a 10% water change yesterday. I am not sure what I should do?? Please help and give any advice. Here are my readings.

nitrate 20 ppm
nitrite 0 ppm
ph 8.2
kh 240 ppm
gh 180 ppm

ammonia it just says near danger zone

 

[Big-j]

Keep dosing the tetra startup, I used a similar product when I started the exact same way you did lol. Do several pwc's to reduce the ammonia level now and do at least 2 50% pwc's everyday. Other than that hope for the best. You never know

 

[glassbird]

Are you using test strips, or drop-type test kits? The strips are infamous for being inaccurate. Do you know about the nitrogen cycle? Lots of info on it here, and it is very important to understand the process. Partial water changes (larger than 10%) with a good dechlorinator (I use Prime) will be the best way to go for now. But do not get any more fish until you get thru the cycle.