Description
Quantum Aqua Pro pH Down 1L — Litre of Freshwater pH Reducer for Large Tanks and Discus Rooms
Discus breeders adjusting hundreds of litres of change water a week buy pH reducer by the litre. Quantum Aqua Pro pH Down 1L (SKU: QA451000) is the largest size of Quantum’s Freshwater Essential Plant Essential Aqua Pro pH Down, a solution of buffered sulphuric acid in deionised water formulated to decrease pH safely. Unregulated pH fluctuates and undermines the biochemical processes of fish, shrimp and plants, so Quantum treats it as a parameter to be held within a published range. The product is rated for planted, fish-only, shrimp and pond systems.
Half a capful, about 5 mL, per 100 L lowers pH by roughly 0.2, added into high water flow without shaking, with a hard limit of 0.3 pH change per day. A fish room adjusting 500 L of change water down by 0.4 uses 50 mL, so a litre covers twenty such batches; a 600 L display corrected by 0.2 uses 30 mL. Quantum’s ranges give the target, 6.0 to 7.0 for South American tanks and 6.0 to 6.8 for high-tech planted among them, and its note that dosage varies by aquarium means testing after every step. The solution is not for dosing pumps.
Usage & Application
When to Use
- Discus and soft-water fish rooms: Adjusting large volumes of alkaline change water each week.
- Large planted displays: High-tech tanks of 400 L and more held at 6.0 to 6.8 for plant growth.
- Shop soft-water systems: Holding tanks for Amazon species on alkaline supply water.
- Several tanks: One bottle correcting a number of aquariums through the week.
Dosing & Administration Guide
- Read the system first: pH and the published range for the livestock kept.
- Half a capful per 100 L: About 5 mL for a 0.2 fall, into the strongest flow, no shaking.
- Maximum 0.3 per day: Big corrections take several days and several tests.
- By hand only: Not for dosing pumps; adjust in increments as results vary between tanks.
Product Specifications & Highlights
Key Features
- Buffered sulphuric acid in solution: A gradual, controlled fall in pH.
- Litre for scale: Twenty 0.4 adjustments on 500 L batches of change water.
- Same strength as the bottles: Half a capful per 100 L still lowers pH by about 0.2.
- Published targets: Ranges for every freshwater tank type.
- Aqua Pro system: The bulk partner to Aqua Pro pH Up, KH and GH.
Product Details
- Brand: Quantum (Freshwater Essential Plant Essential range)
- SKU: QA451000
- Barcode (GTIN/UPC): 0769807350694
- Product Type: Additives & Supplements > Freshwater pH Adjuster
- Net Volume: 1 L
- Contents: Deionised water, buffered sulphuric acid
- Dose Rate: ½ capful (about 5 mL) per 100 L lowers pH by about 0.2
- Capful: About 10 mL
- Maximum Change: 0.3 pH per day
- Target Ranges: South American 6.0–7.0; high-tech planted 6.0–6.8; community and shrimp 6.5–7.5; low-tech planted 6.8–7.5; goldfish and koi 7.2–7.6; African cichlid 7.8–9.2
- Dosing Pump: Not suitable
- Target Environment: Planted, fish-only, shrimp and pond freshwater aquariums


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