6_'
‘
.
'
Tlie' Aquatic Environnent
‘
'
_
ist'ics in cycles, usually annually, and the fishes’ ways,change with
ThuS their breeding period is usually influenCed by the
'
'
ditions which successfully promote the growth of their young and
É
those which are to their own advantage over a long
_
period of time.
_
,
'
,
j
,
One of the difficulties of domestic fishkeeping is that it is virtually
impossible _to reproduce truly in our aquaria the cyclic' changes
Ï
>
which occur
nature. With a little more complex equipment than
is,,geneælly available it would be reasonably easy to arrange,,
a
cycle of…/temperature and light intensity which would reproduce a—
î
natural 24—hour period. But to do. this for each day in an annual
a
cycle would indeed be difficult… We must therefore sort out that
part of
cycle which suits the fish best and concentrate
on producing an environment which approximates to it. This Would
_“
seem to be the time, not when the fish are actually breeding, but in
Ï;
[the preceding period when they are building themselves up into a
suitable condition for spawning. The ability of a fish to get into good
breeding condition
to develop viable Spawn or sperm is a better
indication of the“ suitability of its enVironment than the actual
ir
_
breeding event,‘which often takes place in a different situati0n al—
_
,
together, more suitéd to the protection of the eggs and the growth
of the resulting fry.
'
_
'
,
KEY FACTORS IN THE AQUATIC ENVIRONMENT
_
_
,
The adultbody size of a fish,within the limits of i_tfs,«,_natural
maximum,is 'largelydetermined by the
available
”—
_
space is restricted by the use, of a Small container
by ovei*crowding‘;,f
_
then the fish will be stunted. It is nOt easy
minimum volumes
required per f15h1nchor
Criteria si—nce—othei” faCtÔrS,-…
,
e,gf._t‘he
the available water, ;affeçt theresult,butif-thè
/
is acknowledged:it—Willÿbè seenthhtdueallowancemust
‘ïÏ
be made. An important starting poiijit is to allowasmuchspaceas
P°Ssîbïê bV' pr9vidinçg anaquarmmofadequatesmeAquanaare
hardly ever big enough- tohouse anythmgbmsmallSh,and11@t
_
even large qüantities
thoseOfcourse1fanfïäî@iuaristbnly has,gsay, =
,
a ZO-gallon
_TinfoilBairh—g,_
he Will usually do scandvemuayœme to realise that he hasn0
‘
.
'
Tlie' Aquatic Environnent
‘
'
_
ist'ics in cycles, usually annually, and the fishes’ ways,change with
ThuS their breeding period is usually influenCed by the
'
'
ditions which successfully promote the growth of their young and
É
those which are to their own advantage over a long
_
period of time.
_
,
'
,
j
,
One of the difficulties of domestic fishkeeping is that it is virtually
impossible _to reproduce truly in our aquaria the cyclic' changes
Ï
>
which occur
nature. With a little more complex equipment than
is,,geneælly available it would be reasonably easy to arrange,,
a
cycle of…/temperature and light intensity which would reproduce a—
î
natural 24—hour period. But to do. this for each day in an annual
a
cycle would indeed be difficult… We must therefore sort out that
part of
cycle which suits the fish best and concentrate
on producing an environment which approximates to it. This Would
_“
seem to be the time, not when the fish are actually breeding, but in
Ï;
[the preceding period when they are building themselves up into a
suitable condition for spawning. The ability of a fish to get into good
breeding condition
to develop viable Spawn or sperm is a better
indication of the“ suitability of its enVironment than the actual
ir
_
breeding event,‘which often takes place in a different situati0n al—
_
,
together, more suitéd to the protection of the eggs and the growth
of the resulting fry.
'
_
'
,
KEY FACTORS IN THE AQUATIC ENVIRONMENT
_
_
,
The adultbody size of a fish,within the limits of i_tfs,«,_natural
maximum,is 'largelydetermined by the
available
”—
_
space is restricted by the use, of a Small container
by ovei*crowding‘;,f
_
then the fish will be stunted. It is nOt easy
minimum volumes
required per f15h1nchor
Criteria si—nce—othei” faCtÔrS,-…
,
e,gf._t‘he
the available water, ;affeçt theresult,butif-thè
/
is acknowledged:it—Willÿbè seenthhtdueallowancemust
‘ïÏ
be made. An important starting poiijit is to allowasmuchspaceas
P°Ssîbïê bV' pr9vidinçg anaquarmmofadequatesmeAquanaare
hardly ever big enough- tohouse anythmgbmsmallSh,and11@t
_
even large qüantities
thoseOfcourse1fanfïäî@iuaristbnly has,gsay, =
,
a ZO-gallon
_TinfoilBairh—g,_
he Will usually do scandvemuayœme to realise that he hasn0