I've only had the tank up and running for 16 days. Media is foam with activated charcoal. Haven't cleaned filter yet. Here are the new readings as of this morning.
Also have spinning paper cylinders as media in filter.
I think you may be on to something. I've used flourish in my planted tank and drove my ammonia readings off the chart. But my fish show no sense of distress. Also my Nitrites and nitrate tests show 0ppm readings.
I have a 40L with caribe complete substrate. It is planted well and running on a marine penguin filter. My fresh water ammonia tests are very high. Nitrate and nitrites test 0ppm. Have tried 50% water changes which lowers the ammonia but within a day or two it climbs right back up off the scale...