So, you want to start a Marine
An article by Hennie Landman on keeping a Salt Water Aquarium.
A word of warning: starting and
marine tank cause a serious change in human behavioural patterns - looking
dreamy eyed at your tank for hours on end; phoning your loved ones (or
anyone!) in the middle of the night to tell them about a new polyp, worm,
glowing thingy about 1mm long, ... which you have just discovered; not buying
new clothes, furniture etc. because your tank REALLY needs that new light,
filter, ROCK, etc.... Oh well, maybe you won't get hooked so badly.
Firstly, get some
Most people’s main source of advice is the
Local Fish Store (LFS). Petshops, LFS's, call them what you like, these
shops all exist primarily to make money. If they do, they are successful,
and the owners can live in comfort (or even grow rich ??). If they don't
make money, they go bankrupt. They will always try to sell you the most
expensive (often quite useless), items, preferably something which you will
have to upgrade later (another sale for them...). And these are the good
ones - the bad shops will also sell you incompatible livestock, or diseased
fish, or even fish caught with poisons, knowing that they will die after a
few days. They can then blame it on you (bad water quality, wrong
filter..."you also need this UV steriliser to reduce disease..."
and because you are not sure yourself, you inevitably buy more equipment
(usually also useless). Get the picture..?? So BUYER BEWARE!
People on Internet discussion groups do not
have any financial gain by what they recommend, and are usually impartial,
but there is another problem lurking - Pride. "I use skimmer x, or
pump y, this is the best, use it!" "Oh, I've kept 10
types of Angels, and 4 types of Damsels in a 50 gallon tank for the past 5
years, It’s EASY - you can do it too..." or even worse, "Oh,
I am very successful with keeping anemones. They are easy to keep, I've
had 5 in the last year..."
Advice in books is usually outdated.
Details on the animals and plants tend to stay relevant, but
"technical" issues such as filters, skimming, lighting, etc.
tend to change rapidly, as new equipment and techniques are developed. So,
before you decide on anything technical, query what the books say!
Whilst gathering your information, you must
THINK. Is it logical, does it agree with what other books say, or with the
views of "experts"? You must also get as many recommendations as you
can, and then try to decide what is right FOR YOUR PARTICULAR SITUATION. Even
some of the most notable "experts" on the net, some even with PhD's,
can't agree on "what is right" all the time. They do tend to agree
on the basics, though, so if you get some "way off" advice, you
should be wary.
Deciding on the TYPE of Set-Up
Before purchasing ANY equipment, you should decide on what type of environment
(or set-up) you want. Some may argue that a fish only tank is easier to keep,
as fishes can withstand a greater degree of pollution and water quality
fluctuations. A "reef" tank though slightly more difficult, is much
more interesting, and gives one a greater sense of achievement and
satisfaction. Many people start off with a FO (fish only), only to upgrade to
a reef tank later. This invariably results in some equipment having to be
replaced, because they did not buy "Reef quality" originally. I
would like to suggest that you buy your equipment with a reef tank in mind,
even though you may initially plan to keep only fish.
Is "fish only" easier to keep than
The general statement that "a Fish Only
system is easier to keep" (or that "inverts are a lot harder to
keep") is very misleading, and totally unfair to novice marine aquarists.
Let me explain:
Keeping "easy" inverts, such as some
species of soft corals, cleaner shrimps, Featherduster worms, etc. are
actually easier than keeping fish. They cause much less pollution, and
therefore place less of a bio load on the system, which maker filtration a lot
less critical. They don't get diseases such as "Ich", and many do
not need much feeding either. You do need a minimum amount of light in order
to keep corals and other photosynthetic animals. Fortunately the easier
"low light" softies, such as brown or green Star Polyps (Pachyclavularia
and Briareum spp.), Mushroom corals (Sarcophyton sp.) and Devils Hand or
Finger Leather corals can be kept under normal fluorescent lights - though you
would need quite a few tubes....
The "difficult" part of keeping a
reef tank is when you also want lots of fish in it. This just does not work
very well, and is not to be recommended to newbies. Rather start off with a
"marginal reef" tank, with lots of live rock, a deep live sand bed
substrate (both very important elements of your filtration, as well as being
interesting in their own right), some "easy" soft corals, some tube
worms, etc. and only a few reef compatible fish.
Do your research first, though. Learn as much
as you can about the different filtration methods, compatibility of livestock,
food and feeding, and everything else you can pick up... Then, carefully plan
your set-up, and GO SLOWLY. In this hobby there is a saying:
IN A REEF AQUARIUM, ONLY BAD
THINGS HAPPEN QUICKLY.
If you stock your aquarium before it has
cycled properly, you will probably kill your animals. If you stock too
rapidly, your tank will have another ammonia/nitrite spike, again probably
killing your animals. At best, you will have problem algae, and sick fish.
Remember that this is a long-term hobby. It is not uncommon for a tank to only
stabilise properly after 6 months. Your corals can outlive you, and even the
most common fish can live longer than 20 years, if you do your bit....
Equipment does not *have* to be very
expensive, but it *usually* ends up costing a great deal more than you
originally had in mind.
Tank size and Shape:
Although one could successfully keep very
small marine tanks, this is a specialised field, and is not the ideal for a
Deeper tanks look more natural. They do
require more intense lighting, though. They should also only have the same
bio-load as a regular depth tank of the same surface area.
A larger tank will be more stable, and
forgiving if something goes wrong. A small fish dying in a mature
100-gallon tank would probably not have any effect on the water quality.
That same dead fish would most likely cause an ammonia spike, algae bloom
and possibly further die off if it was left in a 20 gallon tank.
Your fish will be less stressed in a larger
tank (if you don't over-stock), as there is more room to evade aggressors,
and to allow each fish to have it's own territory.
It is also easier IMHO to use a surge
device (wave-maker) in a larger tank. A 20 litre surge discharged into a
200 litre tank will cause a "tidal wave" to overflow the top. In
a 500-litre tank the effect will be less than half, and in a 1000 litre
tank it would probably not even cause a ripple.
A pre drilled tank with an
"overflow" weir is much better than a conventional tank with a
siphon "overflow" to the sump. It allows for a much larger water
flow, and is much safer to use, as there is no siphon that can
"break" and cause the tank to overflow and/or the sump to run
The disadvantages of a larger tank are mostly
It would cost a lot more to fill the tank,
and to do partial water changes
One would require substantially more live
rock, and sand, to achieve a decent looking, and properly filtered tank.
As live rock and sand are amongst the most expensive purchases, a larger
tank would increase the total cost most dramatically.
One would obviously want more corals, etc.
This would be added to over time, so work on a constant, long-term drain
on the wallet.
Practically, it's more difficult to reach
all the "spots" in a large tank when you're doing maintenance
The greater amount of living creatures, and
costly live rock, etc. increases the financial risk of losing a major
investment if there is a long-term power blackout, the tank cracks, an
outbreak of disease, or other disaster. This would cause you to consider
the purchase of "back up" equipment, such as a power generator
if you want to sleep well at nights.
This will depend on the type of set-up:
"Fish Only" (FO) tank only needs
enough light to view the fish comfortably.
If you use "Live Rock" (FOWLR) in
your tank, then you should not have less than 2.5-3.0 W/gal (Watts per
gallon) (more is better).
"Soft" corals such as star polyps
and mushrooms require about 3-4 W/gal (again, more would be better).
Hard corals, clams and anemones need a
minimum of 6-8 W/gal, depending on the water depth.
Normal Output (NO) fluorescent lights are
mostly used on FO or FOWLR systems, but can be used quite successfully on
Reef tanks as well, provided one has the space to accommodate all the
tubes. As an example, I have kept a Carpet Anemone in my marginal reef
tank for more than 8 months, using 8 x 40W NO tubes on my 55 gal. tank. (I
have since upgraded to Metal Halides)
PC (Power Compact) fluorescent lamps are
nearly as bright as Metal Halides, and are quite suitable to keep all
types of marine animals in all but the deepest tanks. They are quite
expensive, though, and not always obtainable.
VHO (Very High Output) fluorescent lamps
are "old technology", and are being superseded by the PC's or
MH (Metal Halide) lamps are the brightest
lamps available, and nearly equal the intensity of sunlight. They are
probably the most suited type of lighting for deep tanks, and for
"Reef" type set-ups with light loving animals such as SPS
corals, clams and anemones.
The light "Colour temperature" is
also very important. Water "absorbs" the longer wavelength light
(the red, orange and yellow colour) at a shallower depth than the shorter
wavelength light (green, blue and violet). If one descended from the surface
of the ocean, the red light would disappear first, and the last light
remaining at depth would be violet.
Sunlight at the water’s surface has a colour
temperature of 6,500K. I don't have exact figures, but I believe that the
10,000K light spectrum approximate a depth of around 10m (33') below the
surface, and the "bluer" 20, 000K spectrum is equivalent of light at
a depth of about 20m (66')
Because *most* corals live closer to the
surface, 10,000K light would actually be more natural for them than 20,000K
light. If one were to set up a "deep water" tank, containing species
living at greater depth than that of a "normal" shallow reef, one
would be better off to use the 20,000K lamps.
The following links may explain this in more
Skimmer - This removes biological waste
before it can decompose into ammonia, etc, and thus lightens the load on
the bio-filter. Do not skimp on the skimmer - buy the best you can afford.
It is perhaps the single most important item you will buy, so rather get
one rated at twice your capacity than get one which cannot cope.
In a lightly stocked tank live rock and/or
live sand "biological" filtration is all that is required (apart
from the skimmer, that is).
In a more heavily populated "fish
only" tank, a Wet/Dry trickle filter is probably the best biological
filter, though it will lead to a higher nitrate level than live rock
Canister filters are good
"mechanical" filters, but they tend to produce an excess of
nitrates in the tank.
Under-gravel filters should be avoided
where possible, as they also produce unacceptably high nitrate levels.
A sump – get the largest practical tank,
plastic container, etc, which will fit below your tank (or anywhere else
that’s convenient). A sump is not really essential, but it does increase
the total water volume, and allows one to keep all the ugly equipment
(such as heaters, chiller, skimmer, and just about anything else) out of
the tank. It is also a great place to make a refugium, and it allows for a
more efficient gas exchange due to the tumbling action of the water
flowing down into it.
It is very important to use pure,
unpolluted fresh water to replace evaporated water, and to make the
salt-water used for partial water exchanges. Using ordinary tap water
invariably leads to algae outbreaks.
RO (Reverse Osmoses) filters are the
cheapest in the long run, and they remove 95% (or more) of the
contaminants from the water.
DI (De Ionisation) filters become exhausted
quite soon, and need frequent replacement. This makes this type of
filtration quite expensive. DI units typically remove 99% of all
contaminants while "fresh".
One can combine the two, first using RO and
then DI. This results in the purest water, but IMO is not really
One could also use a "hand held"
water purifier, such as Nitragon, or a household unit such as the Brita
filter. These units are actually small DI filters, and work quite well
while fresh. Because of their small capacities they are quite expensive,
Heaters: Work on using about 2W/gal to
raise the tank temperature 5 degrees F above the room temperature. (Thus
for a 55 gal. tank you would need ~ 300W to raise the temperature to ~ 75
F if the surrounding temperature is ~ 60 F). It is better to use two or
three smaller heaters than one large one. If a smaller heater fails on, it
is unlikely to boil your tank, and if it fails off the other heater can
still supply some heat until you (hopefully) discover the problem.
Air pumps: This is not normally needed if
you have adequate circulation. It is good to have a standby unit for an
emergency, though. I also use mine to aerate freshly made salt water used
for partial water exchange.
Decorations: These can be anything from mini patio umbrellas to tiny treasure chests."
Thermometer: Get an accurate glass or
electronic one - those little "stick on" types are not accurate.
Hydrometer: These are notoriously
inaccurate. Get a good glass type, and make sure you know for which
temperature it is calibrated.
Pumps – Good water circulation is
essential. Buy a good quality return pump (if you’re using a sump), and
one or two additional power heads. . A "surge" device or "wavemaker"
is a good addition, but is not essential.
Live rock - get about 20% - 40% of the
tank's volume of live rock. This is essential for long term water
stability (read: low nitrate level).
Sea salt – There are many makes of salt,
and not all of them are good. Read the package label, and ask questions on
the Net before you buy it. You will not only need salt for the initial
makeup, but also for regular partial water changes (about 10%-20% of water
volume every 2-4 weeks, depending on stocking level, etc).
"Incidentals" – You will need
some test kits, additives such as buffer and calcium, a fish net, some
containers to mix your water…
To be honest, whenever I hear this term, I
envisage this large, all glass tank, riding around on a bicycle …..
The term "cycling" is actually a bit
of a misnomer, IMHO. In our hobby, it usually refers to a state where the
aerobic component of the filtration system has "matured" to such an
extent that there are enough aerobic bacteria present in the system to convert
the ammonia/um generated by the tank's bio-load into nitrite, and the further
conversion of the nitrite into nitrate. In actual fact, this only completes of
the first phase of the actual nitrogen cycle.
Until a few years ago, that was as far as the
process could go, resulting in a slowly increasing level of nitrate, which
could only be reduced by partial water changes. Thanks to the
"discovery" of live rock, and later of live sand, the
"'cycle" can now be completed by anoxic bacteria living in these
substances, further converting the nitrate into inert nitrogen gas.
In hobbyist’s terms, a new system is
considered to be "cycling" when there are still detectable levels of
ammonia/um and/or nitrite in the water. A system is considered to have
"cycled" when these levels drop to zero, and the nitrate level
starts to increase.
The important thing to remember is that a tank
does not "cycle" only once. The system will reach equilibrium, where
there is enough aerobic bacteria living in the filters to maintain an
undetectable level of ammonia and nitrite with a given bio-load. Any
increase in the bio-load, such as when a new fish is added to the tank, will
upset this equilibrium, by "flooding" the system with more
ammonia/um than the bacteria can digest. Obviously, with more "food"
available for these bacteria, they will multiply (assuming that food was the
limiting factor), and in time the system will reach a new equilibrium, able to
handle this increased bio-load. This does take time, though, and in the
meantime the increased level of ammonia and/or nitrite could be poisoning all
How to "Cycle" a new tank.
In order to "cycle" a new set-up,
one must introduce a source of ammonia/um. In the past, this was usually done
by adding some hardy fish (usually Damsels) to the new tank. Although this
works very well in a bare tank (with outside filtration), it’s not
recommended for two reasons:
It is cruel to keep any fish, no matter
how "hardy" in water containing near toxic levels of
Damsels are very aggressive, and once the
tank has "cycled", they consider the whole tank as their
exclusive territory. They will attack, and possibly kill, any new fish
being introduced to the tank. To make matters worse, the rock in a
typical reef tank makes it hard, if not totally impossible, to catch
them when you eventually decide to replace them.
I would start the cycling by initially only
adding the sand. Let it settle for 2-3 days, with all the circulation going.
Then, add one or two pieces of base quality live rock, and one or two dead
prawns or cocktail shrimps (the food type, not a dead one from a LFS - that
could be carrying any number of diseases!). At this time, start testing the
water for ammonia daily. You should notice an increase in the reading, and
after a few days, the reading should stabilise, and then slowly start to drop
(this could take 1-2 weeks). At that stage, start testing for nitrite as well,
and keep on testing for ammonia. You should now notice an increase in
nitrites, and a decrease of ammonia. After another week or so, the ammonia
level should be fairly low, and the nitrite level should have reached it's
Once the nitrite level has also started to
drop, you can add the rest of the base quality live rock, and once both the
ammonia and nitrite levels have become unreadable low, you can then add the
good quality live rock (containing many interesting inverts). This could cause
another ammonia & nitrite "spike", although it will be much
smaller than the first. This is not critical if you’re patient - just let
the tank settle for another month or two before adding fish. This should give
the macro algae and small critters on the LR time to recover, and to multiply
to sustainable levels in the LR, and to migrate into the sand. During this
time, you should also add some live sand, and/or some live sand "starter
kits" and "reef janitors". Also, don't be concerned with the
initial algae growths - it's quite normal to have some diatom, cyano, and hair
algae growing as the maturation progresses.
"Cycling" a new system with uncured
Introduce the LR after the tank's been up
about a week, and use it to cycle the tank. Wait at least two months before
introducing the first fish.
You don't stress (or kill) any fish, and do
not have to add fish that you will have to remove at a later stage.
You don't need to buy fully cured LR. In
fact, the cheaper, uncured LR causes a better cycle, and usually have more
diverse life forms in/on them.
You can introduce all the rock at once, do
your "rockscaping", and have the tank completely set up when
introducing the first fish.
You will have amazing growth of whatever
comes on the LR - with no fish to eat them, you will get all kinds of
macro algae, featherduster worms, soft polyps, even some corals, growing.
You will also enable the "small
life", such as copepods and amphipods, to establish and multiply to
such an extent that they should survive predation by your fish. Obviously,
if you only have 2 or 3 of a specie to start off with, and they're eaten
by a fish on the very first day, none will multiply after that.
You will have to wait before you introduce
Because the initial bio load was smaller,
you will have to add your fish at a much slower tempo to avoid causing
another ammonia/nitrite spike.
You might have some algae growing on the LR.
This is usually not a problem, though, as you start off with a nutrient
poor set-up, which can be easily maintained, as there are no fish to feed.
Also, the growing macro algae compete for nutrients, thereby restricting
the growth of nuisance algae.
Deep Live Sand Bed filtration:
A general rule of thumb is to have a 4"
layer of fine, graded sand, although the actual thickness would depend on the
size of the sand. The finer the sand, the less water flow is possible between
the particles, and the thinner the layer needed to achieve an anoxic zone in
the sand. IMHO the very small size sand, though "perfect" for
nitrate reduction, is not what occurs naturally, and does not allow hiding
places for many small critters. My sandbed is made up of ~75% natural sea sand
(shell grit and silicon sand, ranging from ~0.5mm to ~ 6mm in size)) and ~25%
crushed coral sand (approximately 1-2mm in diameter). I have found that the
areas containing the coarser particles have a greater abundance of small
Here are some links to interesting articles
(hope they still work...):
Whys and Hows of Sand Beds
Quantitative Comparison of Two Nutrient Removal Systems
It's quite human to want to add all kinds of
things to help our creatures. The manufacturers and shops know this, and make
a lot of money out of this "weakness". Unfortunately, many of these
"snake oils" are just expensive water (perhaps coloured). Others do
add trace elements, but an excess of many of these elements are actually
detrimental to your tank (amongst other things, it tends to make cyano and
hair algae grow...).
Under normal circumstances, one should only
add buffer (to keep the alkalinity up), and a calcium supplement if/when there
are hard corals (LPS or SPS) or other calcium using life forms in the tank.
Either use one of the "balanced" two-bottle supplements, or add
Kalkwasser. If you do not have many calcium absorbing animals (such as
corals), then you probably don't need to add calcium supplements. You then
also don't need those high calcium levels normally quoted for a reef tank.
Note that the long-term addition of calcium
chloride will result in a gradual increase of the chloride content of the
water. This will eventually result in your water's chemistry being quite
different from that of natural seawater, which is not good at all
Apart from this, I would not add any
supplements unless I could test for it, and found a deficiency, as regular
partial water changes would replenish the trace elements used up by the
I realise that I've only skimmed the surface
of starting with this great hobby (pun intended), but I hope that this article
can be of some use to someone out there…