Thats easy - its information,
get informed before a drop of water hits a tank, decide what you want
to keep, is it going to be fish only? or maybe coral only or possibly
a full reef as this will decide what equipment/lighting you should be
aiming for..
A marine tank cycles in different
ways to a freshwater tank, we predominantly use live rock ( which is rock
taken from the ocean) and live sand to help not only cycle the tank but
also process waste products on a constant basis, if the tank is stocked
with approx 2lbs of live rock per gallon it should be able to cycle out
most nitrate that the tank produces if the tank is stocked at a reasonable
level.. plus a marine tank will go through many different cycles, they
usually come as ammonia-nitrite-nitrate, diatoms-algae-hard algae( corraline
algae).
This last stage of diatoms to algae can take some 6 months, especially
if water conditions are bad or cheap sand is used as the free scilicates
in cheap sand will feed the diatom bloom for many months..likewise with
the algae stages, if water quality is less than perfect then algae will
be a big problem possible for years until the source of the food is discovered.
Lastly we have hard algae, this is desirable and a sign of a healthy tank,
hard algae comes in a range of colours from pink to red and purple etc
F ish come in all different shapes and sizes, nearly all marine fish are
classed as delicate, obviously there are a few that are hardier than others
but they cannot and will not suffer bad water conditions or cycling tanks,
therefore just chucking in a few damsels and thinking that they will do
ok isn't usually the case, that's why we use live rock as a cycling agent.
T he general rule for stocking is about 1" of fish per 3 gallons
for fish only systems and 1" of fish per 5 gallons of water for reef
systems, obviously this isn't a rule that's hard and fast, if you have
a thin bodied fish that's 3" long vs a fat fishthats also 3"
long the fatter fish is going to produce more waste, so a bit of common
sense must be used when selecting fish or deciding on stocking levels.
Salt
once again a big section of your tank will be influenced by the salt you
use, there are many
brands available, i have tried some of the cheaper ones as well as the
more expensive ones and there is very little difference in the top end
of salts, but a big difference in the budget end.
I would personally recommend either kent
or the best i have tried is reef crystals
obviously as with most things in life if you buy in bulk it will be cheaper,
i have found it better to go for the 55lb drums of salt and save about
40% on the cost of i bought it in small bags.
Mixing salt is done differently
by everyone, i like to mix my salt in a spare tank/waterdrum as when first
mixed the salt is very caustic, if you are just starting out and the tank
is TOTALLY EMPTY then yes you may mix the salt you need in the tank, get
the temp of the water to 26c ( or the hydrometer wont work properly) then
add salt till you hit about 1.015, leave this mix for 24-36 hours as different
compounds in the salt mix at different rates, after 36 hours all the compounds
should have mixed well and you can retest the sg.. normally it will stay
the same but it may have increased in that time as all the salt mixes
into the water, then slowly add salt til you read 1.022 and stop there,
wait another few days with a powerhead circulating the water, the ph will
be quite high when the salt is first mixed, and it also can give a false
reading for ammonia when just mixed as well so don't be alarmed if you
notice this.
The tank should now be ready for rock and live sand.
mixing salt for water changes..
a little forward planning is usually needed for waterchanges on a saltwater
tank, most keepers know when a water change is due and will plan a day
or 2 ahead making ro water and pre mixing to prevent problems.
S alt mix for water changes are usually done in spare buckets/rubbermaid
tubs or any food grade plastic containers, the salt is mixed in exactly
the same way as the first time you did it, get it to temp then add the
salt, check the salinity of the new water against the older water that's
in the tank to check for compatibility, once they are identical leave
the new mixed water for a day or 2 and keep a eye on its ph, once the
ph of the new mixed water is stable its safe to use( usually 48 hours,
but maybe more for amounts of 50 gallons and above)
Lighting
Your lighting will determine what you can keep in the tank, and opposite
what you want to keep will determine what lights you buy, light is not
only used to view the fish etc, but its also used as a food source for
corals, so the lights must be powerful enough to supply the demand of
what you wish to keep.
normal output tubes (n.o) will suffice for fish only systems, soft corals
will demand either a small bank of several n.o tubes or a few high output
t5's as these deliver more light per watt than a n.o tube will do, hard
corals will demand either a large bank of t5's or the high end of lighting
which is halide lighting.
tanks are calculated on depth for the amount of light needed to penetrate
the water, for every 100w of halide light supplied the penetration is
approx 12" so a 15w light tube is really only going to penetrate
about 3-4" as far as supplying lighting for food goes.
the spectrum of lighting is also important, freshwater tanks use anything
up to 6500 kelvins, but a marine tank will suffer massive algae and look
washed out with such a yellow light, marine tubes are generally 10,000
kelvin's in temp which give a crisp but not yellow light, for a deeper
look to the tank then 14.000k or 20.000k tubes/halides are used( or a
combination of all), this isn't just for appearance the bluer end of the
spectrum is used for corals to convert sugar into food more than the whiter
end, therefore if you do use 6500k tubes then you must supplement the
tank with 50.000k dedicated blue tubes.
Other equipment needed are
the same as any other fish tanks, a good stand, heaters and testing equipment
for salt water especially concentrating on high end ph, nitrite, nitrate,
ammonia are essential, after that calcium, magnesium and iodine aren't
so essential but good to know where you are at... Flow
Flow is mainly produced by means of power heads, reef tanks have quite
a bit of flow to not only stimulate the action of waves but the added
flow also helps with water quality, as the more water is pushed by and
through the porous live rock the faster it will be able to process waste
products.
this
is a standard type of power head -
How many are needed??
this all really depends on what type of tank you have, a fish only tank
will have substantially less flow than a reef tank, especially if there
is less rock in the tank as any structure will dissipate flow quite considerably
so additional pumps may be needed to stop any dead spots from forming
within the tank.
as a general rule of thumb its good to try to cycle the whole tank's gallonage
every 10 mins through power heads..sometimes this will need to be increased
depending on the structure and layout of the tank..
Mechanical
Filtration
Marine tanks are usually very well filtered, this is usually done by skimmers
but some keepers like to use some form of mechanical filtration, any type
of filter can be used but its good to remember that any floss or filter
material should be rinsed in TAP WATER every 3 or 4 days to kill the bacteria
thats living on them, otherwise they will become biologically active and
start to produce nitrates in massive amounts, with obvious results..
Chemical Filtration
T his form of filtration is used more often than any other, products such
as rowaphos or carbon are used to add a sparkle to the water and to remove
impurities and phosphorus from the water.
products like rowaphos can be kept inthe water continuously and need only
replacing when algae returns or traces of phosphorus are detected in tests.
carbon must not be used all the time but in blocks of 2 weeks every few
months, this is to stop it from releasing any impurities it has absorbed,
and to stop it from releasing phosphorus as most carbon is produced from
coconut husks which has a very high amount of algae producing phosphorus..
Live Rock 1 what is it ??
2 what does it do ??
well now for the bit that is totally different to freshwater systems,
a freshwater tank can only cycle ammo-nitrite-nitrate with water changes
used for removal of the end stage, a marine tank filtered with live rock
will cycle ammo-nitrite-nitrate-nitrogen gas+consumption due to anaerobic
bacteria in the cores of the rock, this alone stands a marine tank alone
from all others, the ability to cycle nitrate is a massive boon and is
something that most fish keepers will stock their tanks with rock for
alone irrespective of all of the other benefits.
Live rock is large
hunks of rock that have been taken from the ocean, it is not only full
of billions of bacteria spores, but also home to thousands of small critters/hermits/sponges
and tube worms..in fact the list of life on them is massive, this is why
we pay so much for hunks of rock that look dead.
there re 2 types of live rock available to you, the first is uncured,
this has just been removed from the ocean and contains alot of life but
also quite a bit of dead bacteria and critters that didn't make the flight
over to this county, so it is going to be quite raw and produce a bit
of ammonia when added to the tank..
cured rock is the second type available and as the name says it has had
time to sit in vats of water and get rid of the ammonia that its going
to produce, this rock is a little more expensive simply cos that lfs has
had to keep it for longer and spend cash on salt etc for water changes..
if you use sufficient amounts of live rock ( up to 2lbs per uk gallon)
then mechanical filtration isn't really going to be needed, the rock will
do it for you as long as there is sufficient flow in the tank and it is
cured to a high degree, the bigger the pieces of rock the better its ability
to denitrify, but sadly the more expensive it is as well...
geographical types of live rock..
This
is florida base rock -
its quite dense and liiks alot like concrete, this rock is too dense to
be useful for denitrification as the water cannot penetrate but its useful
for building bases and saving cash if all live rock isn't wanted or if
your stocking a very large system.
Fiji rock is one of
the most common and best rocks to get, its full of nooks and crannies
where life can emerge and is great for filtration -
it can come usually as small cannonball shapes but sometimes is available
as thinner flat pieces, great for making caves.
Eco
System Rock
This is the new craze, when eco warriors complained about the amount of
rock used in the aquatic trade thats taken directly from the ocean, a
new trade developed, and that was to make your own rock, this is then
shaped using a concrete base and cured for many months in varge vats.
its available in some outlets but isn't considered live rock unless its
been allowed to sit in a active system for some time, useful again to
use as a base rock -
Salt
or the best i have tried is reef crystals 
This
is florida base rock - 
Eco
System Rock