Reef Complete

  • Liquid ionic calcium source
  • Most concentrated calcium supplement on the market (160,000 mg/L)
  • 100% soluble. Be wary of products that are milky white or need to be shaken

Reef Complete® is a concentrated (160,000 mg/L) optimized blend of ionic calcium designed to restore and maintain calcium to levels found in natural seawater without affecting pH. Calcium and carbonates are essential to all coral growth. If either becomes deficient, coral growth will cease, followed by a rapid decline in coral health. To prevent this you must provide calcium (Reef Complete®) and carbonates (Reef Builder™ or Reef Carbonate™).

Reef Complete® also includes magnesium and strontium in amounts proportionate to typical utilization ratios (100:5:0.1, Ca:Mg:Sr). This allows one to maintain these two important elements while maintaining calcium.

Reef Complete® is a blended product. It is not simply calcium chloride. Commercially available calcium chloride contains ammonia. Unlike other ionic calcium supplements, Reef Complete® is blended to a higher pH in order to force the ammonia to gas off into the atmosphere. In addition, Reef Complete® is more concentrated than any other liquid product on the market. Reef Complete® contains 160,000 ppm calcium. Our nearest competitor’s product is only 110,000 ppm calcium.

Sizes: 100 mL, 250 mL, 500 mL, 2 L, 4 L


Use 1 capful (5 mL) per 80 L (20 US gallons) twice a week. Check calcium every 2 weeks and adjust amount or frequency accordingly.


Check calcium level (use Reef Status™: Calcium to measure calcium), then follow addition regimen above until calcium is adjusted to 380–420 mg/L. Each 5 mL/80 L (20 US gallons) will raise calcium by about 10 mg/L. Quantity or frequency can be adjusted, but do not exceed 12.5 mL/80 L (20 US gallons) per day. Thereafter, use as required to maintain calcium.


After determining the calcium consumption rate, set up a continuous drip system. Use the following formula (or skip the math and use our Dosage Calculator) to determine how much to add to your top–off water: m=vc/160 (m=mL of product to add to top off water, v=volume of tank in liters, c=amount to raise calcium in mg/L). [For reference: 1 US gallon=3.8 L].


If used with Reef Calcium™, it is not necessary to exceed 380 mg/L total calcium. Use Reef Status™: Calcium to measure calcium.

DO NOT OVERDOSE: Excess calcium may enhance the loss of carbonate alkalinity. Do not directly mix with any carbonate supplement. Best if calcium & carbonate additives are added on alternate days or at least 30 minutes apart.

To reach your desired level use

mL ( caps)

Do not exceed 12.5 mL/80 L (20 US gallons)


Use Reef Status™ Calcium to test calcium levels.

We recommend a Ca level between 380-420 mg/L with an alkalinity between 3-6 meq/L (8-17 dKH). It is advisable to make large adjustments slowly to avoid overshooting intended level or shocking corals and inverts.


Do not exceed 12.5 mL/80 L (20 US gallons). Excess calcium may enhance the loss of carbonate alkalinity. Do not directly mix with any carbonate supplement. Best if calcium & carbonate additives are added on alternate days or at least 30 minutes apart.

A: The type of calcium in Reef Complete® is an ionic form of calcium (calcium chloride) and is easily detected by the available calcium test kits on the market.

A: You can have a successful reef aquarium without the use of Reef Calcium™ as a supplemental source of calcium. The advantage of Reef Calcium™, which is very unique to our company, is that this source of calcium is bound to an easily metabolized carbohydrate. When the coral metabolizes this carbohydrate, which takes virtually no energy from the coral, the calcium goes right along with it. Because of the form of calcium this is, it can not be as concentrated as Reef Complete®. Because of this it is more economical to use Reef Complete® as your primary calcium supplement, but you also derive a benefit when using Reef Calcium™ as a secondary calcium supplement.

A: No, Reef Complete® will not be impacted by a canister or protein skimmer. It is perfectly acceptable to leave this equipment running while dosing this supplement.

A: Reef Complete® is the liquid version of Reef Advantage Calcium™. They are both ionic calcium supplements that also provide magnesium and strontium in typical utilization ratios. Since they both are the same, it simply comes down to whether you prefer liquids or powders. I personally prefer liquid because they are simple to dose and no pre-mixing is necessary. That being said, powders can be very economical. Reef Calcium™ is an organic calcium meant to help maintain calcium levels in a system, while Reef Advantage Calcium™ and Reef Complete® are meant to raise calcium levels in the system. Reef Calcium™ is a poly-gluconate calcium that will provide more calcium to the system without the corals having to expend any extra energy, thus increasing growth and maintaining calcium levels. Reef Calcium™ typically will not be used to raise Calcium in the system, but rather to maintain calcium that is already existent in ideal levels. If levels are not in the ideal range, we would recommend that you use Reef Complete® or Reef Advantage Calcium™ to boost calcium levels.

Can't find what you're looking for? Ask us a new question. One of the experts from our technical support staff will be happy to promptly respond. You can also call 888‑732‑0003 (Monday- Friday 9:00 AM - 5:00 PM EST) if you would like to speak directly with a technical support representative.

Amounts per 1 g
Calcium (Ca) (min) 155 mg
Calcium (Ca) (max) 160 mg
Magnesium (Mg) (min) 8 mg
Strontium (Sr) (min) 0.16 mg

Ingredients: Calcium Chloride, Magnesium Chloride, Strontium Chloride

Download Safety Data Sheet (SDS)

CAUTION: Causes serious eye irritation. Keep out of reach of children. Avoid contact with skin.

0335 Reef Complete 100 mL
0336 Reef Complete 250 mL
0333 Reef Complete 500 mL
0338 Reef Complete 2 L
0339 Reef Complete 2 L