"—
_
1
..
—
ghting“
'
87
should be remembered that where aqùaria are mounted one above
another any tungsten lamps in the loWer installations will tend to
heat the upper containers by convection, unless some insulation is
fitted…
"
…
Nowadàysmanÿ aquarists use uorescent lighting because of its
several advantages. Originally the types of tubes available did not give
off a natural kind of light and were so déficient in certain parts of
the spectrum that plants would not ourish. Better tubes are now
available in the domestic rangé (Table 8) and, in addition, special
'
Table 8. LIGHT OUTPUT* OF FLUORESCENT TUBES
Length (in.)
'
‘
Standard
Miniature
__Tÿpe
60 +
60
48
86
24
18
21
12
9
_
Wattage
'
65
50
40
30
20
15
13
8
6
4
White
4700 3300 2750 1850 1100
750
730
360
240
135
'
Warm White
4600 3250 2700 1850 1100
750
730
360
240
135
Daylight
4450 3200 2650 1750 1050
700
680
340
230
125
Natural
8400 2400 2100 1400
800
550
_
280
190
100
Northlight/
Col. Match
2700
1700 1050
700 450
_
—
—
—
Articial .
,
.
Daylight
2100
_
1200
—
500
__
—
—
—
—
[ Grolux ;
j;,1450118004
810
530
840
200
180 100
—
—
*In lumens
New tubes will be._'10—20% brighter.
+ Super 5
_
_: 80w 35 65W
-_…Î
'
'
'(C…… Thorn Lighting)
€
<;
_
.
Grolux
,
tubes are recommended evenwheïeplantsarentgT@wn’as
number Of tÿpiœï tubes
shown
Figurê«f34
Eluorescent lighting" is not‘cheap to
use and the replacement rate is uSually very10w Itproducesun_
heat at amuch lower rate than tung8ten
andgenerates/
r‘rnoreÇ—lightgper Watt of p‘oWerçonsumed bythetube The tubeg1ves
-agood i‘diSp‘éf5î‘0'n of 1fi‘î8htbut thepowerlsgovemedbÿthelength
ofthe tube
it is
for instance, to have…a“50 Wtu6