just got in and tested the water and after shaking the test tube for the first time in a long time it was still yellow. YEA!!!. It started to pick up on orange tint after a few minutes though. So tonight another 8 gallon change and replace the filter media and test again tomorrow. But for the first time I feel like I am winning the war. I am doing a tone of water changed to beat this thing (replace the filter media every time too not just rinsing). If I can keep the color yellow it will have been worth it.