Seachem Prime Water Conditioner 250ml

Seachem Prime Water Conditioner 250mL – Trusted Aquarium Water Conditioner for Clean, Safe Tanks

Seachem Prime Water Conditioner 250mL is the bottle you grab when your tap water is playing dirty. It neutralizes chlorine and chloramine on contact and detoxifies ammonia, nitrite, and nitrate—without throwing your pH out of whack or causing your skimmer to go wild. If you’ve got fish and you’re using untreated tap water, this is the safety net.

It’s not new or trendy. It’s just reliable—and every tank should have it.

How Seachem Prime Helps Your Fish Tank Stay Balanced

Plenty of aquarium water conditioners claim they “remove chlorine,” but Prime goes further. It also makes ammonia and nitrite non-toxic, giving your filter time to catch up—especially during new tank cycling or after unexpected spikes. And if you run a reef tank, you’ll appreciate that it doesn’t over-activate your skimmer like cheaper alternatives can.

Quick rundown:

• Removes chlorine and chloramine from tap water

• Detoxifies ammonia, nitrite, and nitrate for up to 48 hours

• Won’t mess with pH or water parameters

• Safe for use in freshwater, saltwater, and reef setups

• Supports tank cycling without interfering with your filter

Seachem Prime 250mL Is Extremely Concentrated and Budget-Friendly

This isn’t one of those “use half the bottle per water change” products. One capful (5 mL) treats 50 U.S. gallons, so the 250mL size covers up to 2,500 gallons. That’s months of protection in a single bottle.

Directions (no fancy chemistry degree needed):

• 1 capful (5 mL) per 50 U.S. gallons of new water

• Each cap thread = roughly 1 mL for smaller tanks

• Add to new water before adding it to the tank when you can

• In emergencies (like a surprise ammonia spike), safely dose up to 5x

• If the water’s over 86°F and ammonia is low, go with half a dose

You might notice a sulfur smell—that’s normal. It’s the active ingredient doing its job, not a reason to panic.

Use Prime During Water Changes, New Tank Setups, or Any Time Things Get Sketchy

This isn’t just a conditioner—it’s your emergency backup plan. Whether you’re introducing new fish, doing a large water change, or trying to ride out a nitrite spike during cycling, Prime helps keep your tank livable.

Even if you're running a high-end reef system or a beginner freshwater setup, it slots in with no drama. It plays nice with biofilters, doesn’t kill bacteria, and doesn't trigger weird chemistry chain reactions. Just dose it, and get back to enjoying your tank.

Product Specs – Seachem Prime Water Conditioner 250mL

• Size: 250 mL (treats up to 2,500 gallons)

• Safe For: Freshwater, saltwater, reef tanks, planted tanks

• Formula: Liquid, non-acidic, concentrated

• Item Weight: Approx. 0.6 lb

• Dimensions: 6.3″ L × 2″ W × 2″ H

• SKU: 116043405

• UPC: 000116043405

Final Thoughts on Seachem Prime Water Conditioner 250mL

If you’re setting up your first tank or maintaining a reef with thousands invested, Seachem Prime Water Conditioner 250mL gives you control over what’s in your water. It's reliable, easy to dose, and doesn’t overpromise—it just does what it's supposed to do.

And honestly, for what it does, it should probably cost more.

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