THE AQUARIUM BUILDING
I9
Tlie latter is associated with the water's ability to
maintain a stable pH and especially to avoid drastic
drops of pH in unflushed tanks. At a methyl orange
alkalinity of less than 25 p.p.m., it is desirable to add
finely ground calcium carbonate to unflushed tanks.
CARBON dioxide: Carbon dioxide frequently
occurs in well and spring water. Fishes commence to
exhibit effects of it at 50 p.p.m., and it is advisable to
maintain the concentration at a level below 30 p.p.m.
even though fishes can survive at higher concentrations. The most efficient way to remove carbon dioxide is to spray the water into a louvered tower. It can
also be chemically removed with hydrated lime or trishydro-xymethyl-aminomethane (for use of latter see
Chapters).
iron: Iron, principally in the form of ferrous
bicarbonate, is a common contaminant of weU and
spring water. When this water first comes from the
ground, it is clear, but upon being aerated the ferrous
bicarbonate, at least in neutral and alkaline water,
forms a hydrated oxide in the form of a brown precipitate. In the dissolved state, i.e., ferrous bicarbonate
form, iron is a mild irritant to fishes. The hydrated
oxide is not toxic but causes marked turbidity and
badly stains tanks and equipment.
For low concentrations of iron (less than 5.0 p.p.m.)
and for limited water requirements (less than 1,000
gallons per day ) iron filters designed for home use are
quite satisfactory. These filters utilize manganese
zeohte which can be regenerated. For high concentrations of iron and for large quantities of water it is
I9
Tlie latter is associated with the water's ability to
maintain a stable pH and especially to avoid drastic
drops of pH in unflushed tanks. At a methyl orange
alkalinity of less than 25 p.p.m., it is desirable to add
finely ground calcium carbonate to unflushed tanks.
CARBON dioxide: Carbon dioxide frequently
occurs in well and spring water. Fishes commence to
exhibit effects of it at 50 p.p.m., and it is advisable to
maintain the concentration at a level below 30 p.p.m.
even though fishes can survive at higher concentrations. The most efficient way to remove carbon dioxide is to spray the water into a louvered tower. It can
also be chemically removed with hydrated lime or trishydro-xymethyl-aminomethane (for use of latter see
Chapters).
iron: Iron, principally in the form of ferrous
bicarbonate, is a common contaminant of weU and
spring water. When this water first comes from the
ground, it is clear, but upon being aerated the ferrous
bicarbonate, at least in neutral and alkaline water,
forms a hydrated oxide in the form of a brown precipitate. In the dissolved state, i.e., ferrous bicarbonate
form, iron is a mild irritant to fishes. The hydrated
oxide is not toxic but causes marked turbidity and
badly stains tanks and equipment.
For low concentrations of iron (less than 5.0 p.p.m.)
and for limited water requirements (less than 1,000
gallons per day ) iron filters designed for home use are
quite satisfactory. These filters utilize manganese
zeohte which can be regenerated. For high concentrations of iron and for large quantities of water it is