Red Sea Salts - 2 kg (60 Ltr Bag)
Pack size
2 kg bag
Cost per litre
$0.35
Water type
Marine + Reef
Red Sea Salts - 2 kg (60 Ltr Bag)
Balanced reef-grade seawater you mix fresh, right before it goes in the tank. Red Sea Salt is a premium marine salt mix built around a consistent calcium, alkalinity and magnesium balance rather than a headline number alone, so a bucket mixed today reads close to the last one. This 2 kg bag is the nano and top-up size – enough for a small water change or two, not a full system mix.
Key features
- One salt, three targets – the same formula mixes to a lighter fish-only salinity, a mid invertebrate salinity, or full reef salinity, just by changing how much you dose. See the mix ratio table below.
- Dissolves fast and clear – no cloudiness or residue once mixed and aerated.
- Free of nitrate and phosphate – won't feed algae or push a reef tank off balance on day one.
Mix ratio and resulting parameters
| System type | Dose | Salinity | Calcium | Alkalinity | Magnesium |
|---|---|---|---|---|---|
| Fish-only | 33.4 g/L | 31.0 ppt | 365–395 mg/L | 6.8–7.3 dKH | 1,100–1,180 mg/L |
| Non-coral invertebrates | 36.0 g/L | 33.5 ppt | 390–420 mg/L | 7.3–7.8 dKH | 1,170–1,230 mg/L |
| Coral and reef | 38.2 g/L | 35.0–35.5 ppt | 415–445 mg/L | 7.7–8.2 dKH | 1,240–1,320 mg/L |
Add salt to water, not water to salt. Mix vigorously without aeration for 30 minutes to 2 hours until the pH settles at 8.2–8.5, then bring the mix to tank temperature and check salinity with a refractometer before use.
Which pack size is cheapest per litre?
| Pack | Litres at reef salinity |
|---|---|
| 2 kg bag | ~52 L |
| 4 kg bag | ~104 L |
| 22 kg bucket | ~575 L |
The 4 kg bag is actually the cheapest per litre of the three sizes we stock – not the bucket. If you're topping up a nano tank or trying this salt for the first time, the 2 kg bag is still the right call; for anything you'll be mixing regularly, the 4 kg is worth stepping up to before the 22 kg bucket.
Suitable for, and not suitable for
Suitable for fish-only, invertebrate and coral/reef marine systems – the target salinity changes, the salt doesn't. Not a substitute for Coral Pro Salt if you're chasing higher baseline alkalinity for SPS-heavy growth; the two can be swapped between, but only gradually (max 15% of a water change at a time) because of the alkalinity step up.
Care and maintenance
Store the sealed bag somewhere dry – a damp storage area will clump the salt before you get to use it. Mix in a clean, dedicated bucket and let the water reach tank temperature before dosing, to avoid a temperature shock on the tank it's going into.
Warranty and delivery
Sold as a consumable, not a warranted item beyond your consumer guarantee rights under Australian Consumer Law – if a bag arrives damaged or short-filled, contact us for a replacement.
Common questions
Is Red Sea Salt reef safe?
Yes. It's designed for fish-only, invertebrate and coral/reef systems alike – mixing it to a lower or higher salinity target changes which system it suits, not the formula itself.
How much water does a 2 kg bag actually make?
Around 52 L mixed to full reef salinity (38.2 g/L). Mixed lighter, for a fish-only tank at 33.4 g/L, the same bag goes further – about 60 L.
What's the difference between this and Coral Pro Salt?
Coral Pro Salt carries a higher baseline alkalinity aimed at faster SPS coral growth. Elemental composition is otherwise similar, and you can switch between the two – just do it gradually across water changes rather than all at once.
Do I need a refractometer to use this?
Yes – a swing-arm hydrometer isn't accurate enough for reef salinity. We stock a seawater-calibrated refractometer if you don't already have one.
