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Useful Information
Alkalinity - measures the amount of acid required to neutralize the alkaline salts such as carbonates or bicarbonates present. Recommended level 8.0 - 12 DKH. The buffer is the sum total of the carbonates and bicarbonates in the water, these constitute the buffering capacity of the water, also acid binding capacity. This is in essence the ability of the water to deal with the continuous production of acids of all kinds, including course, the carbonic acid generated by the addition of CO2. Should this buffering capacity become too low, the ph will start falling, and the fall is the pronounced, the lower the buffer or carbonate hardness is. Hardness - refers to the total amount of dissolved mineral salts in water such as carbonates, bicarbonates and sulfates of calcium, magnesium and other salts. To find the calcium ion concentration you need to multiply the calcium carbonate equivalents value by 0.4. Aquarium levels have ranged from 288 to 390 mg/L, you should use calcium chloride (calcium chloride di-hydrate) to raise the calcium level to between 420 and 450 mg/L. Once the desired level of calcium is attained you can then use the calcium hydroxide solution to maintain it. Carbon Dioxide - is dissolved in water either as CO2 of H2CO3 (carbonic acid). Carbonic acid disintegrates into hydrogen ions (H+) and bicarbonate ions (HCO3-). The bicarbonate ions eventually dissociate into carbonate ions (CO3-) and hydrogen ions (H+). All these are so called equilibrium or reversible reactions - that is, they move forward or are reversed according to prevailing conditions. Dissolved Oxygen - in sea water at 75 degrees F will contain about 6.8 mg/L of dissolved oxygen at 100% saturation. Under increasing temperature, oxygen decreases by 10% for every rise of 9 degrees F. Phosphate - inorganic phosphate in marine water consists of hydrogen phosphate HPO4, di-hydrogen phosphate H2PO4 and phosphate ion PO4. These phosphates are commonly called "ortho-phosphate" and is the primary source of phosphate for marine algae. Recommended level below 0.05ppm PO4. Total Dissolved Solids- actually measures conductivity but is calibrated with sodium chloride solution so that TDS is expressed in ppm of NaCl. Conductivity is calibrated with potassium chloride but is expressed in micro siemens. Formulas for converting Conductivity and Total Dissolved Solids Salinity - acceptable levels, 25 ppt - 1.018 SG, 35 ppt - 1.026. Freshly mixed s.w. has a orp value 230 - 245. SALTS which make up seawater in descending order of concentration - sodium chloride (NaCl), magnesium chloride (MgCl2), magnesium sulfate (MgSO4) calcium sulfate (CaSO4), potassium sulfate (K2SO4), calcium carbonate (CaCO3), potassium or sodium bromide. pH - expresses the relative proportions of acid hydrogen ions (H+) and alkaline hydroxyl ions (OH-), when CO2 decreases the equilibrium of the pH shifts towards the right or alkaline side of the scale (water becomes more alkaline). When dissolved CO2 increases the pH drops and the water becomes less alkaline or more acid. Reverse Osmosis - drops the ionic strength of the feed water by filtering out the ions of the dissolved salts present. As a result of this, the hardness is also reduced. Reverse osmosis is a filtering process which removes dissolved salts and molecular compounds present, producing a softer water as a product. Deionization - reduces the ionic strength of the water by removing all the dissolved salts. A deionizer is commonly composed of two separate cylinders: a cation cylinder which removes all of the cations; and the following anion cylinder which removes most anions if it is the common weak anion resin. The weak base anion resin will not remove the bicarbonate ion, HCO3-. The acid from the cation resin causes the bicarbonate ion to hydrolyze to free carbon dioxide, CO2. To remove the CO2, the water must be strongly aerated for at least six hours before it could be pumped into the fish tanks. Ozone - 1 mg. of ozone per 1 gal. of water with an air dryer. 2 mg. of ozone per 1 gal. of water without an air dryer. |