New 20g tank
I used to have fish when I was a kid. Now I have kids of my own, so we got a 20 gallon tank. It been running for 5 weeks. Things are going okay, but I changed the filter yesterday and my nitrites are way up. I didn't realize having a healthy tank was so much work! I've since read here not to toss out old filters or risk problems. Wish me luck. Hope I don't lose any fish with this nitrite spike.