New Tank Cycle Trouble

[boberga]

So 3 weeks ago my dad bought me a 30 gallon tetra starter kit with 3 angelfish. A week later my mom and sister bought 3 guppies 2 mollys and a platy (both mollys where from pet smart the rest where from flea market). I never knew about cycling a tank and I always hear people talk about how liquid test are better then strip tests so after 1 of my mollys died and the other was about to die my sister returned the mollys to get cash back but I told her to get the api master water test kit. So I tested the water (3 week old, set up tank) and it said the ph was 7.5 ammonia was 0 ppm Nitrate 40 ppm Nitrite 2.0 ppm
I asked what to do and I was told to do a 75% water change. So I did that and later I got a response telling me that I was having a cycling issue so I decided to post here right before I fall asleep since it's 11:30 pm here. I just did another test right now (a couple of hours after changing the water) and ph was 7.4 ammonia 0 ppm Nitrate 2.0 ppm Nitrate 160 ppm. What do I do?!??!?!

I can't get rid of the remaining fish cause no one will take them. I don't understand stand why the Nitrates quadrupled and I don't know what to do now

To keep on record here this is what I have right now
20 gallon tall tank with led hood kept on for 10-12 hours a day or left off with sun light.
Tetra whisper pf20 filter
Tetra whisper air pump 20
100 watt heater
25lb gravel
4 fake plants.
Top fin water conditioner
Top fin tropical flakes
3 guppies 3 juvenile angelfish the size of a toonie and 1 red wag tail platy
Api water master test kit
Tank is now been running for 3 weeks with fish since the first day

 

[Byron]

You have the same issue in another thread, here
http/www.fishforums.net/index.php?/topic/438601-tank-trouble/
to which several members are responding.  It is best to keep an issue in one thread to avoid confusion, repetition and ensure a better response from everyone.  So I suggest you not proceed with this thread, but only the linked thread.
 
Byron.