Soft Water Mineralisation Wild Caught Protocol Guide: GH Booster
Pure RODI water reads zero TDS and contains nothing — no calcium, no magnesium, no trace minerals. Drop a wild fish straight into it and you create the opposite problem from hard tap water: severe osmotic stress from a complete lack of dissolved ions. Soft water mineralisation wild caught protocols rebuild that water deliberately, adding back the minerals fish need without overshooting into the high-GH range that breaks blackwater chemistry. This guide from Gensou Aquascaping at 5 Everton Park covers the booster products, the target parameters and the testing routine that makes this work.
Why RODI Is the Starting Point
RODI (reverse-osmosis deionised) water provides a known-zero baseline, removing chloramine, heavy metals, phosphates, nitrates and dissolved organics from PUB tap. Building up from zero gives precise control over final chemistry. Most SE Asian and South American wild fish thrive at TDS 30-100 — a target almost impossible to hit by diluting Singapore tap because the starting baseline is already at TDS 80-120.
The GH Booster Products
Salty Shrimp Bee Shrimp Mineral GH+ adds calcium, magnesium and trace minerals without raising KH. This is the standard for blackwater shrimp and wild fish where KH must stay near zero. Salty Shrimp Bee Shrimp Mineral GH/KH+ adds both — appropriate for harlequin rasboras, gouramis and species needing mild buffering. Seachem Equilibrium provides an alternative with similar effect, though slightly less precise dosing.
Target Parameters for SE Asian Wild Fish
Most SE Asian wild blackwater species: GH 2-4, KH 0-1, TDS 80-120, pH 5.5-6.5. South American Amazon blackwater: GH 1-3, KH 0-1, TDS 50-100, pH 5.0-6.0. Heckel discus and Rio Negro endemics: GH 0-1, KH 0, TDS 30-60, pH 4.5-5.5. Match the species’ origin water rather than picking a generic blackwater target.
Mixing the Water
Fill a clean 25-litre container with RODI. Add GH booster per the manufacturer’s dosing — typically 1g per 10 litres lifts GH by roughly 1 degree. Stir thoroughly, wait 30 minutes for full dissolution, then test with TDS meter and GH/KH test kits before adding to the tank. Pre-mixing is essential — never dose boosters directly into the tank with fish present.
Testing Equipment
A TDS meter (SGD 25-40 from Lazada or local fish shops) gives instant feedback on overall mineral content. GH/KH liquid test kits from API or Sera (SGD 15-25) confirm specific hardness. A digital pH probe is valuable for blackwater systems below pH 6.0 where colour-change indicators become unreliable. Browse the aquarium pump range and accessories for water-care kit.
Tannin Loading After Mineralisation
Mineralise first, then add tannins. Indian almond leaves, alder cones and peat moss from the decoration and substrate range drop pH after mineralisation is set. Adding tannins to unmineralised RODI gives unpredictable pH because the buffer system is unstable.
Maintenance Routine
Weekly 25 per cent water change with prepared water mixed to identical parameters as the tank. Test TDS, GH and KH on both source water and tank water before every change. Drift in tank parameters between changes signals biological load issues — restrained feeding and consistent maintenance hold the chemistry steady.
Common Mistakes
Over-mineralising past target TDS is the most common error — once minerals are in, they only come out via dilution with more RODI. Add boosters incrementally and re-test rather than aiming for the full dose at once. Using PUB tap as a “convenience cut” with RODI also disrupts the calculation because tap water carries unknowns like chloramine that can interfere with sensitive species.
Singapore Practical Notes
RODI cartridges run SGD 60-150 for under-sink units capable of producing 50-100 litres per day. Marine reef shops at Pasir Ris, C328 and Serangoon stock them. Salty Shrimp boosters are widely available at SGD 35-60 per 850g tub, lasting six to twelve months for typical wild-fish keepers. Browse the fish food range for additional wild-fish nutrition options.
When Not to Mineralise
Fish from hardwater habitats — Tanganyikan cichlids, South Chinese karst-stream species, Central American livebearers — need full hardwater chemistry, not soft-water mineralisation. Match the protocol to the species’ native water profile.
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emilynakatani
Still Have Questions About Your Tank?
Drop by Gensou Aquascaping — most walk-in questions get answered in under 10 minutes by someone who has set up hundreds of tanks.
5 Everton Park #01-34B, Singapore 080005 · Open daily 11am – 8pm
