I've only had my tank for less than 2 months but my water parameters was stable for at least 3 weeks until now. I bought some plants last week and added a bunch of root tabs for them. Because of these changes, I've been monitoring my water parameters more often. Last week, the ammonia and nitrite were 0ppm. The nitrate was around 5ppm. Yesterday, my ammonia and nitrite were both 0ppm, while my nitrate was at 20ppm. Today, everything spiked so the ammonia and nitrite were about 1ppm and the nitrate was probably around 80ppm. I immediately did a water change but the water parameters are still in dangerous levels for the ammonia and nitrite. I've dosed seachem prime to protect the only betta fish in the tank and will probably do another water change tomorrow.
What could have possibly caused this crash? There were maybe a few leaves that melted but nothing else seemed to have died. Are there any other suggestions in order to get this cycle back to normal quickly besides adding bottled bacteria, which I've already done?