You can use API General Cure to help you fish ward off fish lice, gill flukes, hole-in-the-head, skin flukes and velvet. So, can this product harm the beneficial bacteria living in your fish tank?
You can find out in this article from Aquarium Blueprints.
Quick Summary
API General Cure will most likely not harm the beneficial bacteria or disrupt the biological filtration in your fish tank.
If you do notice spikes in ammonia, nitrites and/or nitrates, then we recommend dosing Seachem Prime every 48 hours to detoxify these nitrogen compounds. We also suggest dosing Seachem Stability so that you can quickly add more beneficial bacteria in your aquarium.
Can General Cure disrupt the biological filtration?
According to API, General Cure should not harm the beneficial bacteria in your fish tank as long as you follow the dosage instructions correctly.
How to tell if there is a disruption in your biological filtration
Although it is highly unlikely General Cure will disrupt the biological filtration in your aquarium, we still recommend testing your water parameters to see if there are any issues with the water quality just to be sure that your pet fish aren’t being exposed harmful elements.
Ideally, the water in your aquarium should have 0 ppm of ammonia, 0 ppm of nitrites as well as less than 20 ppm of nitrates.
Spikes in these nitrogen compounds may not necessarily mean that it was the result of using General Cure. Instead, the increase could be related to a fish death, overfeeding and other scenarios.
You should also keep in mind that you will need to remove any activated carbon from your filter in order for General Cure to remain effective. Since beneficial bacteria also live on the carbon media, then you will be removing a portion of your biological filtration.
What to do when your biological filtration gets disrupted
If you notice a spike in ammonia, nitrites and/ or nitrates during the middle of the API General Cure treatment process, then we recommend using a product such as the Seachem Prime. This water conditioner will help detoxify ammonia, nitrites and nitrates for up to 48 hours.
You can keep adding Seachem Prime every 48 hours, to prevent the nitrogen compounds from harming your already sick fish.
For a faster way to reduce ammonia, nitrite and nitrate in your fish tank, we recommend using a product like the Seachem Stability. This product contains live bacteria that will quickly reestablish your biological filtration.