During-effort fuel · electrolyte · reviewed 26 Aug 2026
SiS GO Hydro 44
102 mg of calcium a tablet, several times any other product here, alongside a moderate 345 mg of sodium, at $2.17 per 1000mg of sodium.
Score breakdown
The overall score is the average of what's below, each measured against every other electrolyte we've reviewed.
44
Mixed
Sodium dose ?Sodium per serving, on a scale topping out at 1000 mg — a single dose covering the top of what's typically lost to sweat in an hour.35
Value (cost/1000mg Na) ?What it costs to get 1000 mg of sodium from this product. Not physiological -- a market-based scale from $3.00 (0) to $1.00 (100).41
Potassium ?Potassium per serving, on a scale topping out at 200 mg — roughly the upper end of typical hourly sweat loss.33
Calcium ?Calcium per serving. Weaker grounding than sodium/potassium -- sweat calcium loss is minor and not really a primary target during exercise; the 100 mg ceiling is this catalog's practical high end, not a physiological one.100
Magnesium ?Magnesium per serving, on a scale topping out at 60 mg, roughly matching cited hourly sweat-loss ranges.13
Cost per 1000mg sodium
$2.17/1000mg
Sodium per tablet
345mg
Comparison
5 of 11 electrolytes heldPrices per single sachet at the cheapest box size we track. Best in green, worst in red, across the gels shown.
| Measure | Science in Sport SiS GO Hydro | LMNT LMNT Citrus Salt | Nuun Nuun Sport | Precision Fuel & Hydration Precision Fuel & Hydration PH 1000 | 4Endurance 4Endurance Electrolytes |
|
|---|---|---|---|---|---|---|
| SodiumThe main electrolyte lost in sweat, and the biggest single driver of cramping and hyponatremia risk. | 345 mg | 1000 mg | 300 mg | 500 mg | 250 mg | |
| PotassiumWorks alongside sodium in muscle and nerve function. | 65 mg | 200 mg | 150 mg | 130 mg | 70 mg | |
| CalciumInvolved in muscle contraction; lost in far smaller amounts than sodium. | 102 mg | 0 mg | 13 mg | 20 mg | 10 mg | |
| MagnesiumSupports muscle and nerve function; some evidence it blunts cramping. | 8.1 mg | 60 mg | 25 mg | 10 mg | 50 mg | |
| CarbohydrateMinimal by design. This is a hydration product, not a fuel source. | 0.9 g | 0 g | 4 g | 3 g | 0 g | |
| Price per tabletWhat one tablet costs. | $0.75 | $1.50 | $0.75 | $1.20 | $0.27 | |
| Cost per 1000mg sodiumThe only price that compares across different sodium concentrations. | $2.17 | $1.50 | $2.50 | $2.40 | $1.08 |
Verdict
what it does · what it costsWhat it does well
- 102 mg of calcium, by far the highest of any electrolyte product reviewed.
- 345 mg of sodium at a reasonable $2.17 per 1000mg.
- Sold in tubes of 20, the largest bulk size here alongside Nuun.
What it costs you
- Only 65 mg of potassium, the lowest of the tablets that declare it.
- Fortified with B-vitamins (riboflavin, thiamin, B6) that add ingredients without changing the core electrolyte profile.
- US retail pricing for this product is harder to pin down than the US-native brands here.
Where to buy
Prices and links as last checked.
Who this is for
the numbers, appliedThe field tells you what it is. This is who should act on it.
Worth the money if
- Calcium specifically is a priority for you alongside sodium.
- You want a large tube size at a moderate per-dose price.
Look elsewhere if
- Potassium is the electrolyte you're most trying to replace.
- You want the single cheapest cost per 1000mg of sodium in this set.