GH+ shrimp mineral

Performance & sizing

Core numbers for matching this unit to your tank and electrical plan.

Power

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Flow rate

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Noise

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Dimensions

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Price range

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Tank fit (L)

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Consumables & maintenance

Follow the manufacturer schedule for seals, impellers, media, and other consumables.

Description

General hardness is the measurement this product exists to move, so start there. FAO's aquaponics manual defines GH as the amount of calcium and magnesium ions present in water, with iron a minor contributor, measured in milligrams per litre, and keeps it separate from carbonate hardness, which is the buffering side and the one tied to pH. Rainwater is low in hardness because those ions are not in the atmosphere. Reverse osmosis water starts at the same place for the same reason. Hard water, in the manual's words, is a useful source of micronutrients and has no health effects on the organisms, and calcium in the water can stop fish losing other salts. Its scale reads soft below 60 mg per litre, moderately hard 60 to 120, hard 120 to 180, very hard above that. For the animals this bottle is aimed at, this catalog has gone looking for a published mineral figure on several passes and come back with nothing. That is no longer quite true, though the species is not the one on the shop shelf. FAO's manual for farming the giant river prawn tells the farmer that if the water supply is very soft, hardness is raised by adding calcium sulphate; that a total hardness of around 50 to 100 mg per litre as calcium carbonate is ideal for freshwater prawn grow out; and that 2 mg per litre of gypsum lifts total hardness by 1 mg per litre. That is a real target for a farmed freshwater decapod, and Macrobrachium rosenbergii is not Neocaridina or Caridina. Neither manual names either genus, neither offers a calcium to magnesium ratio, and neither connects hardness to moulting, which is the claim these products are sold on. Treat the figure as a bearing rather than a dose: buy a remineraliser that publishes its composition, mix it into a measured volume, and read the result on a test kit instead of trusting the scoop.

Sources

• openknowledge.fao.org — https://openknowledge.fao.org/server/api/core/bitstreams/b4d230a3-75b3-45fd-9ebd-7d6ec869ec8a/content/y4100e08.htm
• openknowledge.fao.org — https://openknowledge.fao.org/items/e4d11efd-d97a-4959-8ae2-8b7d3fd32c5e

Figures on this page were read off these pages. Manufacturers and databases do change or retire pages; if a link is dead, tell us with the correction link below.