Dose Your Bacteria Starter
Cycling a new tank, or reseeding after a clean? Pick your product and enter your tank volume.
FAQ
Do I need a bacteria starter for a new tank?
It's optional but genuinely useful – these products let you add fish much sooner than waiting for a tank to cycle naturally (which can take 4-6 weeks), by seeding the filter with the bacteria that break down ammonia and nitrite. You should still test water daily rather than assuming the starter has fully done the job.
Can I use these in an already-established tank?
Yes – they're commonly used after a big water change, a filter clean or replacement, a course of medication (which can harm filter bacteria), or whenever you're adding a larger number of new fish at once.
Why does Seachem Stability have a different dose for Day 1 versus the rest of the week?
Day 1 needs a bigger initial seeding dose to establish the bacteria population; days 2-7 top it up at a lower maintenance rate while the colony grows. Dosing the Day 1 rate every day isn't how the product is designed to be used.
Is bacteria starter the same as a water conditioner?
No – they do different jobs. A conditioner (see our Water Conditioner Calculator) neutralises chlorine, chloramine and heavy metals; a bacteria starter seeds the beneficial bacteria that process fish waste. Most new-tank setups use both together.
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Dosing rates above are each brand's own published figure. Using a different product? Check its own label – rates and schedules vary.