Foundation guide / UK

Calcium, alkalinity and magnesium test kits

These three measurements are often grouped together because coral growth and dosing can move them together. They are still separate tests, with separate errors, consumables and decisions.

What each test is for

ParameterDecision it informsCurrent manual examplePractical note
Alkalinity / KHWhether carbonate demand and dosing are moving the system’s buffering reserveSalifert KH around £8.29Often the most useful frequent trend in a dosing reef
CalciumWhether calcium consumption or salt changes match the system planSalifert calcium around £12.49Check before changing calcium dosing; record the unit and resolution
MagnesiumWhether a lower-frequency foundation measurement is driftingSalifert magnesium around £11.60Usually a slower-moving check unless a known imbalance exists
Digital routeRepeatability and easier reading rather than a different chemistry goalHanna HI-REEFKIT £504.48 inc VATPremium cost; reagents remain a recurring expense

Titration versus digital

Manual titration is inexpensive and gives you a visible endpoint; digital checkers reduce colour-matching judgement and can make repeated readings easier. Neither method is immune to sampling, cleaning, timing or reagent errors. Choose the workflow you will repeat, not the method with the most impressive display.

Test before you dose

When starting or changing a two-part, balling or reactor system, test first, make one measured adjustment, then test again after the interval recommended by the additive maker. Changing calcium, alkalinity and magnesium together from one surprising result makes the cause of the next reading hard to identify.

Build a sensible kit

  • Low demand or fish-first system: alkalinity and calcium can be enough to start, with magnesium as an occasional check.
  • Mixed reef with visible consumption: keep all three, but test alkalinity more often than magnesium.
  • Premium digital route: budget replacement reagents and a backup manual method for a sanity check.

Sources and limitations

Red Sea lists Foundation Pro as a Ca/KH/Mg product family at its Reef Care range. Current UK examples include Salifert listings, Red Sea Foundation Pro and Hanna HI-REEFKIT. We have not independently tested kit agreement or endpoint visibility.

PERIODIC CHECK

ICP adds a laboratory snapshot—not a replacement routine.

Use it when a broader diagnostic view is worth the cost and you can interpret it alongside your own logs.

Understand ICP testing