General Hardness

General hardness (GH)-Measured in mg/l or ppm. Mainly a test for freshwater aquaria. Test kits are used to measure this most often. General hardness is the measure of calcium (Ca++) and magnesium (Mg++) ion concentrations dissolved in water. These minerals are present in well, and bottled spring water.

General Hardness (GH)
GH primarily measures calcium and magnesium ions. It is important for breeders (some species require very soft water, which is hard to maintain, requiring constant monitoring for maximum success).

General Hardness - The measure of calcium (Ca++) and magnesium (Mg++) ion concentrations dissolved in the aquarium water.
Heater - An electrical device used to heat the aquarium water.
Hydrometer - A device for measuring the specific gravity of a marine tank. Invertebrate - Creatures without a backbone.

~ (GH) Kit
You may want to get one of these, but having one is not critical. You don't need to know the exact hardness level. Knowing whether your water is ``soft'', ``very soft'', etc. is good enough. Your local fish store may be able to give you sufficient information.

~
~, or gH as it is also known, is primarily the measure of calcium (Ca++) and magnesium (Mg++) ions in the water. GH is commonly expressed in parts per million (ppm) of calcium carbonate (CaCO3) or degrees hardness (dH).

*GH (~): 100 ppm or sometimes higher; this is more important than many realize for planted aquariums.

GH or ~. . ~ is a measure of a group of dissolved ions that have a +2 charge on them in the water. The vast majority of those ions are either calcium or magnesium, so it is often thought of as a test for just those two ions.

~ (GH) measures the cations (+ charge); for calcium and magnesium.
Carbonate Hardness (KH) Refers to only the bicarbonate, and carbonate anions(-charge); it does not measures the sulfates and other anions.

~ is what people means when they say this fish lives in soft water or hard water.
You can see ~ measured in dH or ppm (part per million of CACO3)
1dH = 17.8 ppm ...

~ (GH) - the measurement of the dissolved minerals in the water expressed in degrees; also called total hardness
GPH - stands for Gallons Per Hour; measurement of the overturn rate of a mechanical filter; the rate at which a mechanical filter filters x amount of gallons of water in a one-hour period ...

GH
~. The measure of overall concentration of calcium, magnesium, and other minerals.
GPH
Gallons per hour of water flow.

GH : ~ - the hardness of your water.
GPH : Gallons Per Hour - the measurement of a filtration system's turning over of water.
Gills : How fish extract oxygen from the water.

GH : ~ (magnesium and calcium carbonate). Some fish (Discus for example) require a very soft water (low GH values, 1-4) while others require a high GH (like African cichlids from the Rift Lakes; values over 12 recommended).

gH - ~ - also called dgH or °gH (degrees of ~). GH is a measure of the concentration of dissolved ions in tank water.

GH is the ~ of the water. Humans can notice difference in water GH when they drink from the tap compared to filtered water. Tap water can be hard, which essentially means it is full of dissolved minerals. Soft water is at the other end of the spectrum and is devoid of minerals.

Unlike the ~ (GH) which is used to describe fresh water, carbonate hardness (CH) is used in sea water, where it serves to measure the quantity of calcium and magnesium carbonates and bicarbonates present.

Glossary: ~
Measure of the overall concentration of calcium, magnesium and other ions in a water sample with values usually quoted in units of degrees (dGH), of which 1 dGH corresponds to 17.848 ppm. Also referred to as total or permanent hardness.
Glossary: generic name ...

Carbonate hardness is mostly calcium carbonate (CaCO3) which comes from chalk and limestone and can be removed from water by boiling. A higher level of CaCO3 in water means the water has a great buffering capability and the pH will be more stable than water with lower KH.
~ includes all minerals ...

Of the two types, there is ~ (GH), which refers to the total quantities of ions dissolved in the water and Carbonate Hardness (KH - the standard adopted is German, in which 'carbonate' is spelt with a K...) which deals with the proportion of Hydrogencarbonate ions, HCO3-.

Aquarium hobbyists should set up an aquarium water testing schedule testing for Ammonia, Nitrite, Nitrate, pH, Phosphorous and ~.

Hardness can be split into ~ (GH) and carbonate hardness (KH).
hardness, carbonate (KH): the concentration of specifically carbonate mineral compounds (carbonates and bicarbonates) within aquarium water.

Carbonate Hardness and ~
The two different types of hardness KH and GH are often confused. Carbonate hardness is the concentration of carbonates (CaCO3) in the water and ~ refers to the dissolved minerals like calcium and magnesium in the water.

Get water test kits that will test the ~ and the Alkalinity of the water. You want both readings to be 0. If the test readings start to trend higher you will know that you soon need to replace the membrane and/or cartridge.

The hardness of water refers to the amount of dissolved minerals in it, and it's measured in two ways: ~ (GH) and Carbonate Hardness (KH). The former measures magnesium and calcium, while the latter measures carbonate and bicarbonate ions.

It's engineered to lower the pH and ~ (GH) of the water (this effect is not to be confused with the lowering of pH associated with adding CO2; simply lowering the pH using Aquasoil is not adding any CO2!). Most plants grow better at a lower pH of about 5.5-6.5.

Although this raises the salinity of water, it does not provide the same benefits of increase ~ (dH), Carbonate Hardness (KH), or any of the other trace minerals that is found in brackish water.

The black phantom tetra is an egg-scattering species. To stimulate breeding, lower the pH to about 5.5-6, and decrease the ~ of the water to below four degrees. The breeding tank should have plants, both rooted and floating, and low light.

The term 'dH' is never truly defined (it means 'degrees of hardness'), and ~ and German Hardness could both be abbreviated as 'GH'. Reagents do not have an expiration date. Titration endpoint is very apparent and 'clean'. Lab ware (a vial) is relatively large and easy to handle.

Test Kits: In order of importance: PH (possibility of hydrogen), ammonia, nitrite, nitrate, GH (~) and KH (carbonate hardness)
Knowledge of the Nitrogen Cycle and how it relates to fish tanks. There's answers here, in the FAQ and all over the Internet.

It almost goes without saying, then, that it does not belong with soft water plants like Tonina and Eriocaulon species. A ~ of around 10 dGH and a pH of 6.6 and above are recommended.

Temperatures in their native lake dip down to about 57 - 64° F (15 - 18°C) around that time, so this seems to encourage spawning. Some suggest that providing a period of cool temperatures in February helps, and that they will fail to spawn at temperatures in excess of 77° F (25° C). The ~ of the water ...

5-6, and decrease the ~ of the water to below four degrees. The breeding tank should have plants, both rooted and floating, and low light, a female black phantom tetra will produce about 300 eggs.