I have used dr Tim’s before and it worked fine. This time I have set up an Im 25 gallon lagoon and started the tank and started using dr Tim’s 3 weeks ago. It’s started fine but now it’s been 2 weeks since my last ammonia dose and my ammonia is super high and hasn’t dropped at all. My question is, did it kill the beneficial bacteria? What do I need to do to fix it? I already did a 20% water change. Do I need to restart with a new bottle of dr Tim’s ? Do I need to drain most of the water and start over? Should I wait?