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Reefstead
Water Chemistry

Water Chemistry

Water Chemistry for reef and saltwater aquariums.

15 articles3 products

Can You Use Distilled Water in a Saltwater Tank Instead of RO/DI?

Distilled water is purified water by the FDA's definition and works for salt mixing and top-off; the question is volume. When jugs beat a 75 GPD RO/DI unit, why tap water is the real risk, and how to mix with either.

Reef Tank pH Too Low? Causes and Fixes That Actually Work
Updated 1mo ago

Reef Tank pH Too Low? Causes and Fixes That Actually Work

Reef tank pH running low? Indoor CO2 is almost always the cause. Ranked fixes: fresh air, skimmer intake lines, CO2 scrubbers, refugiums, and kalkwasser.

Reef Tank Parameters Chart: Every Target Number in One Place
Updated 2mo ago

Reef Tank Parameters Chart: Every Target Number in One Place

The complete reef tank parameters chart: salinity, alkalinity, calcium, magnesium, pH, nitrate, and phosphate targets, plus a testing schedule that works.

Reef Salt Mix Comparison: Parameters, Price per Gallon, Consistency
Updated 1mo ago

Reef Salt Mix Comparison: Parameters, Price per Gallon, Consistency

Four reef salt mix types compared on mixed parameters, batch consistency, and true price per gallon — and how to match the bucket to your tank's targets.

Kalkwasser 101: The Old-School Doser That Still Wins
Updated 2mo ago

Kalkwasser 101: The Old-School Doser That Still Wins

Kalkwasser delivers balanced alkalinity and calcium while raising pH, for pennies. Learn the right mix ratio, drip-dosing safety, and its real limits.

Is ICP Testing Worth It? What a Lab Panel Really Tells You
Updated 2mo ago

Is ICP Testing Worth It? What a Lab Panel Really Tells You

Is ICP testing worth it for a reef tank? What mail-in lab panels really measure, what they miss, and the testing frequency that makes the cost pay off.

How to Raise Alkalinity in a Reef Tank (Safely)
Updated 2mo ago

How to Raise Alkalinity in a Reef Tank (Safely)

Raise reef tank alkalinity safely: the 7-11 dKH target range, baking soda and soda ash dosing math, and the 1 dKH per day rule that protects your corals.

How to Lower Phosphates Without Starving Your Corals
Updated 2mo ago

How to Lower Phosphates Without Starving Your Corals

Lower phosphate in a reef tank the safe way: targets of 0.02-0.1 ppm, GFO and lanthanum used correctly, and how to stop before you starve your corals.

How to Lower Nitrates in a Reef Tank (Ranked by Effort)
Updated 2mo ago

How to Lower Nitrates in a Reef Tank (Ranked by Effort)

Every proven way to lower nitrates in a reef tank, ranked by effort: feeding fixes, water changes, skimming, refugiums, and carbon dosing done safely.

Best RO/DI Systems for Reef Water
Updated 2mo ago

Best RO/DI Systems for Reef Water

RO/DI systems for reef tanks compared — 4-stage 75 GPD units, 5-stage dual-DI, compact apartment rigs, booster pumps, and the TDS meter that runs them.

Best Reef Test Kits: What to Trust Your Corals To
Updated 2mo ago

Best Reef Test Kits: What to Trust Your Corals To

Reef test kits ranked by the job: alkalinity titration, Ca/Mg combos, digital checkers, master kits, and low-range nutrient tests worth trusting corals to.

Best Dosing Pumps for Two-Part & Trace
Updated 2mo ago

Best Dosing Pumps for Two-Part & Trace

Dosing pumps for reef two-part compared — single-head, 4-head programmable, and WiFi dosers — with calibration habits and the ramp-up that avoids overshoot.

Why Does Alkalinity Keep Dropping? (Consumption, Explained)
Updated 1mo ago

Why Does Alkalinity Keep Dropping? (Consumption, Explained)

Falling alkalinity means your reef is growing. Learn where alkalinity goes, how to measure daily consumption in four days, and how to match dosing to it.

Alkalinity vs. pH: What's the Difference in a Reef Tank?
Updated 1mo ago

Alkalinity vs. pH: What's the Difference in a Reef Tank?

Alkalinity and pH are related but measure different things. Learn what each number means, how CO2 links them, and which one to act on when corals struggle.

Two-Part Dosing for Beginners: Setup, Math, and Ramp-Up
Updated 2mo ago

Two-Part Dosing for Beginners: Setup, Math, and Ramp-Up

Two-part dosing for beginners: measure your reef tank's alkalinity demand, calculate exact daily doses, and ramp up safely by hand or with a dosing pump.

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No Water

A nostalgic fish tank lamp with no water and no mess, sold by Linda's Essentials as a decor piece.

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Useek Auto Top Off for Saltwater Aquarium Water ATO System for Both

Useek Auto Top Off for Saltwater Aquarium Water ATO System for Both

Useek Auto Top Off for Saltwater Aquarium Water ATO System for Both

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Fauna Marin Reef ICP Total Test

Fauna Marin Reef ICP Total Test

Fauna Marin Reef ICP Total Test

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