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How much and how often should you use Seachem Pristine?

With Seachem Pristine, you can add beneficial bacteria to your fish tank that will breakdown organic wastes, which will help reduce the amount of ammonia, nitrite and nitrate levels being produced.

You can take a look at this guide from Aquarium Blueprints to see how much and how often should you dose Seachem Pristine for your aquarium.

What are the packaging sizes for Seachem Pristine?

You can purchase Seachem Pristine in bottles that are 100 mL, 250 mL, 500 mL, 1 L, 2 L or 4 L.

Does Seachem Pristine expire?

Because it contains bacteria, Seachem Pristine will eventually expire. Therefore, it is recommended that you use up all the bottle within four years of the listed manufacture date.

How often should you use Seachem Pristine?

You should add a full dose of Seachem Pristine to your fish tank in the beginning to help kickstart the beneficial bacteria. It should take up to three days for the colonies to establish themselves and help with improving the water quality of your fish tank.

After the initial full dose, you can add a half dose of Pristine after the following the scenarios:

1. Adding new fish to your tank.

2. Thoroughly cleaning your tank.

3. Adding medicine with antibiotics to your tank.

4. Any time you believe that the biological filtration in your aquarium has been disrupted. You can use a test strip to see if there is any ammonia and/or nitrite present. If there is, then it is a good idea to add more Pristine to your tank.

As we stated above, it can take up to 72 hours for the Pristine bacteria to establish in your aquarium. Therefore, we don’t recommend dosing this product more than once over a three day span.

How much Seachem Pristine should you use per gallon in the beginning?

The official dosage instructions for Pristine mentioned that you should add 5 mL for every 20 gallons of water in your fish tank when you are using this water treatment for the very first time.

You can find the dosage calculations for most common tank sizes, in gallons, below:

  • 2.5 gallons = 0.625 mL
  • 5 gallons = 1.25 mL
  • 10 gallons = 2.5 mL
  • 15 gallons = 3.75 mL
  • 20 gallons = 5 mL
  • 25 gallons = 6.25 mL
  • 29 gallons = 7.25 mL
  • 30 gallons = 7.5 mL
  • 40 gallons = 10 mL
  • 50 gallons = 12.5 mL
  • 55 gallons = 13.75 mL
  • 65 gallons = 16.25 mL
  • 75 gallons = 18.75 mL
  • 90 gallons = 22.5 mL
  • 125 gallons = 31.25 mL
  • 150 gallons = 37.5 mL
  • 180 gallons = 45 mL

If your tank size does not appear in the aforementioned list, then you can multiply 0.25 mL by the number of gallons your tank can hold to get the needed dosage.

How much Seachem Pristine should you use per gallon for maintenance?

As we stated above, Seachem also recommends adding more Pristine every time after you decide to add new fish to your aquarium, clean your tank, use antibiotic medicine, etc.

For maintenance, you should dose half the normal amount, which should translate to the following:

  • 2.5 gallons = 0.3125 mL
  • 5 gallons = 0.625 mL
  • 10 gallons = 1.25 mL
  • 15 gallons = 1.875 mL
  • 20 gallons = 2.5 mL
  • 25 gallons = 3.125 mL
  • 29 gallons = 3.625 mL
  • 30 gallons = 3.75 mL
  • 40 gallons = 5 mL
  • 50 gallons = 6.25 mL
  • 55 gallons = 6.875 mL
  • 65 gallons = 8.125 mL
  • 75 gallons = 9.375 mL
  • 90 gallons = 11.25 mL
  • 125 gallons = 15.625 mL
  • 150 gallons = 18.75 mL
  • 180 gallons = 22.5 mL

If you don’t see your tank size above, then you can simply multiple 0.125 mL by the number of gallons your tank can hold to get the recommended maintenance dosage.

How much Seachem Pristine should you use per liter in the beginning?

If you are measuring your tank size using the liter metric, then you can check out the calculations for the recommended Pristine dosage when you are using this product for the first time below:

  • 10 liters = 0.625 mL
  • 20 liters = 1.25 mL
  • 40 liters = 2.5 mL
  • 60 liters = 3.75 mL
  • 80 liters = 5 mL
  • 100 liters = 6.25 mL
  • 116 liters = 7.25 mL
  • 120 liters = 7.5 mL
  • 160 liters = 10 mL
  • 200 liters = 12.5 mL
  • 220 liters = 13.75 mL
  • 260 liters = 16.25 mL
  • 300 liters = 18.75 mL
  • 360 liters = 22.5 mL
  • 500 liters = 31.25 mL
  • 600 liters = 37.5 mL
  • 720 liters = 45 mL

If you don’t see you tank size above, then you need to multiply 0.0625 mL by the number of liters your tank can hold to get the recommended initial dosage.

How much Seachem Pristine should you use per liter for maintenance?

For maintenance, you can check out the calculations for the most common tank sizes below:

  • 10 liters = 0.3125 mL
  • 20 liters = 0.625 mL
  • 40 liters = 1.25 mL
  • 60 liters = 1.875 mL
  • 80 liters = 2.5 mL
  • 100 liters = 3.125 mL
  • 116 liters = 3.625 mL
  • 120 liters = 3.75 mL
  • 160 liters = 5 mL
  • 200 liters = 6.25 mL
  • 220 liters = 6.875 mL
  • 260 liters = 8.125 mL
  • 300 liters = 9.375 mL
  • 360 liters = 11.25 mL
  • 500 liters = 15.625 mL
  • 600 liters = 18.75 mL
  • 720 liters = 22.5 mL

If you don’t see your aquarium size, then you can multiply 0.03125 mL by the number of liters your fish tank can hold to get the recommended maintenance amount.