”
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..
—
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for’ any length of time and" thus reliable equipment shoùld“béùs'ed,
With an emergency air Supply always available.
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_
ln marine environments the biological system has the added
advantage that natural coral sand can be uSed instead of stone gravel
and this sand helps to maintain the chemical stability of the salt,
water. However, some coral sand on sale has a rather small grain size ‘
“for efficient circulationand it is worthwhile taking the troubleto
obtain a larger size if possible.
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,.
.
—
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-
Àir in '
Air/Water out
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‘
'.—'.“'fÎ"”-‘.‘°”:ÿà$ “r…—- '.“ü—"":"J'"'*‘ ";:
’î..’$E‘:ä‘$Ï°'ï—à
«..‘._ï_.“.‘3Q.’
‘
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sub—gravelfilterplate‘
-
—
…
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;
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Fig, 9. The_marine biological system. The nitrifying potential of thiseriÿironment
_
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is so high that someoverfeeding, and even dead ‘fishes, càh__be tolerât‘ed; These
;
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happenings
to be‘enc0uraged,but they do‘-demdnstrate
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,
.
_
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to cope With Common
’
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‘
AS we'll.as acting as a bigiogiÇal,.filter the gravel bed‘zis also an
filter. Gradually the spaces in— ithe“ “be—d fillup‘
With detritus from the water and this material is also
bacteria, thereb‘y adding to the nitrifying
Cloggmgcan
occur—Where an“ excess-of detritus_is present_but in this event
-
problem is usually caused by using gravel with too small
Ï The design" of the filter plate it-Self=and its‘_ztssOciated air—lift system
affects efficiency” and thisïis
82)
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Ifa ”bed __is_:waslfedg :for‘ any
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shoŒd…bedone With mature Water—' of the
asthatnrmally
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W1th the bed, :siC'e - .,otherwise$m0‘st»
bacterial ppulat1®n ;
.
…;culd
e çbured‘rj0jf.
st ‘Washihg removesalotofthebactea
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anyway ”b ut reasonable—, care will leave ‘
se noughforagoodstarttoläe
’
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f
made on;:ireihStallatioh; When }6mp tymg an}?
t 01 k eîep“ the
wateI,1f1n good Cond1tlon, and use it to wash th e
ThIS prO
th@r@ughlyscauredbvfreshtapwater *
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