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Equipment '
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Table 5. RECOMMENDED HEATER WATTAGES
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Dimensions
Recommended Wattage
_—
;
18X10X 10
_
'
18 x 12 x 12
50
-
_
24 x 12 x 12
75
_
“ _
x 12 x 12
100
-
36 X 12 X 12
‘
'
150
48 X 12 X12
'
200
It must be noted that these recommendations are for aquaria in
warm
locations, and are only approximate, so that any slight
variation from the sizes shown would be adequately catered for
by the same value. In cold locations higher values should be used
,
and generally, unless the location is extremely cold, that shown for
the next size up is satisfactory. The use of two small heaters instead
'
of one large one has the advantage that there is still some heating
capacity if one heater fails.
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Thermostats
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To control the temperature accurately a bi-metallic thermostat is
c0mmonly used (Figure 16). The bi-metallic switch consists of two
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Connections Out
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,
»
Temperature adjustment screw
-Bi-metallic strip
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Contacts
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’
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Magnet,
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'
‘
_
_
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Fig. 16.1nternal construction of a simple thermostat
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