Short answer by setup
For a moderate, general-purpose reef route, Aquaforest Reef Salt offers a relatively low checked pack price and a stated 33 ppt mixing recipe. Red Sea Coral Pro is the higher-alkalinity choice in this comparison. Tropic Marin PRO-REEF is positioned around lower buffering and calcium-reactor use. Red Sea Salt sits closer to a moderate-alkalinity approach for fish, invertebrates, soft corals and lower-nutrient systems.
| Salt / checked UK price | Stated yield or mixing basis | Published chemistry example | Intended fit | Best suited to |
|---|---|---|---|---|
| Aquaforest Reef Salt 25 kg £74.90 | About 390 g per 10 L at 33 ppt; roughly 641 L by calculation | Ca 410–440 mg/L; Mg 1300–1380 mg/L; KH 7.4–8.2 dKH listed | Mixed reef and aquacultured coral systems | Best value-style reef comparison if the stated 33 ppt mix suits your plan |
| Red Sea Coral Pro 22 kg £74.99 | 660 L stated by current UK retailer listings | Elevated foundation elements; around 11–12 dKH at 34 ppt in the listed table | Mixed reefs, LPS/SPS and frag systems | Best for a higher-alkalinity, coral-growth-oriented salt |
| Tropic Marin PRO-REEF 25 kg £89.99 | Yield depends on the pack’s mixing ratio; compare your actual dosage | Around 7 dKH, 440 calcium and 1350 magnesium in the UK listing | Reef systems where lower buffering and reactor compatibility matter | Best suited to a lower-alkalinity approach |
| Red Sea Salt 22 kg £74.99 | 660 L stated by a current UK retailer listing | Moderately elevated foundation elements; around 8 dKH in the listed product guidance | Fish, invertebrates, soft corals and lower-nutrient SPS | Best when you want a closer-to-natural, moderate-alkalinity route |
Do not compare dKH without comparing salinity
A salt can list a different alkalinity because the target salinity differs. Compare the manufacturer’s table at the salinity you actually plan to run, then verify the first mixed batch with a calibrated refractometer and test kit. A number copied from a bag is not a guarantee for your mixing vessel.
Changing salt without creating a chemistry swing
Use the new salt for a planned water change, test the replacement water and the tank, and avoid changing dosing at the same time unless the measured trend requires it. If the new mix has higher alkalinity, the same percentage water change can move the tank more than expected.
Sources and limitations
Product guidance was checked against Aquaforest Reef Salt, Red Sea salt mixing guidance and current UK listings from Kraken Corals, Shirley Aquatics and Finest Aquatics. We have not independently tested dissolution, batch consistency or coral response.