CORNER" by Kirk Masters
Preservation and Quality Care of Our Reef Friends
You may see some advice that seems to be more than what our corals and rocks get in the
ocean. What we are trying to recommend is called Primary Care or the best preventative
care that you can give your new pets. If we wait for our corals to start to die first then
we have not been proactive in providing the best care available. It is not costly to do
so, but it is costly Not to do so. Most of us try to operate our cars at their maximum
efficiency. We can do that in our tanks by setting up the chemistry very simply and
effectively to maximize calcification and growth. Twenty years ago to keep these life
forms alive was almost unheard of. Today, we can even propage, take cuttings and give
small corals away to our friends.
Water for the Reef Aquarium:
Is any old water okay for a Reef tank? Can you use tap water? Yes, but lets look at what
happens in a Reef tank. My 90 gal tank evaporates about 1 gal per day. I add
Ultra-Kalkwasser (Calcium hydroxide powder) to this makeup water. The high pH of the water
precipatates most of the heavy metals, iron, magnesium, some lead, copper and most
importantly phosphate ( by forming Calcium Phosphate which is a solid material). We are
left with a calcium hydroxide solution with silica and strontium hydroxide in it plus some
nasties we dont want in our water from pollution in the lake. We are lucky that the
lake water is normally very low in nitrates (thank you algae and zebra mussels). Most of
what is left is good for our use. If I add 1 gallon each day I concentrate the bad stuff
by 400% over one year not accounting for some small monthly water changes. You can see
that in a fresh water aquarium we can change 20% of the water per week and get rid of the
concentrating effect that evaporation causes. Using Ultra-Kalkwasser helps a lot but
doesnt get rid of everything. (I will talk about Kalkwasser later). We are both
lucky and unlucky. Today there is a simple solution and relatively low cost compared to
only a few years ago. That is the use of a reverse osmosis membrane system. By using our
tap water pressure it forces the water through a special thin film membrane (TFM) and gets
rid of 98% everything good and bad. We can even go one step further and remove everything
by adding a demineralizer unit after the RO unit. There are many different manufactures on
the market. The best ones use TFM (thin film membranes). I use a DI unit for my tanks to
get rid of all of the silica but you may not have to use one. One can always start a Reef
without an RO unit and add one later like I did. Remember to use a TFM and not the cheaper
cellulose units. SpectraPure has a very good name in the industry. Their DI units are
suppose to have a much longer life than other units (500-600gal). If you use city water
then all you need is a combination carbon and sediment filter in front of the TFM. This
lowers your cost. If you have well water the iron could be a problem and a pre-filter is
in order. The city filters our water and basically all we have to do is to remove the
chlorine(carbon does this in the mixed filter). The sizes vary from 10 GPD to 50 GPD. If
you keep the temperature about 85 F you can increase your throughput. I use a 35gpd
because I dont like to wait too long for my water. Many people are told that you can
soften your water with peat or other chemicals. The truth is these things do not work.
They do not remove the hardness ions (calcium and magnesium). Using a demineralizer
without an RO would last about 5-10 gallons or so. RO units are used world wide to remove
the salt from ocean water. If you remove the alkalinity with the use of an acid or the
addition of a buffer, over a very short period of time the CO2 from the air changes to
bicarbonate alkalinity and we return to where we started from. When I started to use RO
water for my fresh water tank in Kitchener where the water is very hard, my plants started
growing fantastically and the pH of my Angel fish tank dropped to around 7 or lower. My
sword plants had over 60 leafs and looked great. Lighting was two small full spectrum
standard watt actinic and daylight bulbs. (Tip: Use a new electronic ballast will greatly
enhance bulb life, output will be maintained over a longer period. Hair algae was minimal.
Water changes were about 20% per week RO water.
In a Reef we add light and other things to keep the corals and coralline algae growing.
Those beautiful reds, purple, green and white rocks are covered with coralline algae.
These are calcium based life forms and hence use a lot of calcium up. In an ocean we have
a little life with lots of water. In our tanks we have lots of life and a little water. We
2. Alkalinity(also known as buffer or pH)
3. Trace elements
4. Food for the fish.
5. Food for some special corals.
That seems simple enough. We want to maintain a rather high pH of 8.4 (8.2-8.5 max.). This
is easy to do. All we have to do is to add a level teaspoon of that Kalkwasser in a gallon
of water, shake like heck and wait for it to settle for a couple of hours. It can then be
dripped into the tank (using a pump or IV dripper line type of systems one drop at a time,
all available locally). TOO fast a feed rate will kill everything if the pH gets too high.
This is very good for hard stony corals, clams (those beautiful yellow, blue, brown
tridacna clams not the ones you eat). A tridacna clam not only is a wonderful thing to
have in a Reef (I have 2) but they help to lower ammonia and nitrate levels. If you
remember we talked about the Berlin type system. That is live rock and a protein skimmer.
A good protein skimmer aerates the water about 2 tank volumes per hour giving us excellent
carbon dioxide balancing. The dissolved CO2 reacts with the calcium hydroxide to give us
calcium bicarbonate or our alkalinity. What we end up doing is setting the conditions in
the aquarium for optimum coral calcification (pH=8.4 or dKH = 15 degrees). Now what is
that darn dKH? It is the way the Germans use to measure the alkalinity in water. It is
called degrees German hardness like it because we can talk about small numbers 8 or 16
verse 137 or 274ppm bicarbonate alkalinity. I believe in KISS. Keep It Short and Simple.
Testing therefore is one drop per 5mls gives 1 dKH. Do you need a pH meter at first? No. A
pH meter is a great way to monitor your tank without lifting a finger or doing testing on
a more frequent basis. Yes I use a pH meter and an ORP meter, but that is to get all of
the information I can so that I can evaluate what is happening. Get a pH meter down the
road, you will love it.
Understanding our water chemistry is all about understanding what happens to the dissolved
carbon dioxide gas in water. The more CO2 we have as bicarbonate alkalinity the higher the
pH. They (pH & alkalinity) are related in an open system but can have subtle changes
in an aquarium. Bicarbonate alkalinity is the Bus that carries the calcium. For every
calcium ion it has a spare seat.(also for strontium a similar metal ion to calcium). Along
side of calcium is magnesium. In sea water magnesium concentration is 3.5 times that of
calcium. It is because of magnesium the calcium ion concentration can reach over 550 PPM
in a Reef tank (control above 425 PPM). Think of magnesium as one of the driving wheels on
the BUS. Like a busy city, there are about 4 times as many people waiting for a seat on
the bus as there are seats. The remaining calcium (waiting for a seat) is in the form of
chlorides and sulfates.
Sea water can be divided into major, minor and trace elements according to the level of
the elements dissolved in it. The major elements are sodium chloride (35,000 PPM),
magnesium (1450 PPM), calcium (425 PPM), potassium (400 PPM), sulphates. Nothing could be
easier to keep our salt at the right level. We use a simple hygrometer that floats a
needle pointing to the specific gravity. Same idea as testing our battery or water in our
radiator or making wine.
The minor elements are strontium (8 PPM). Too difficult to test for now. Just add
regularly is good enough.
The trace elements are the rest. We need these to live also. Some we need some we
dont. Iodide and iron are the most important of the trace elements and need to be
replenished as protein skimming and activated carbon tend to lower their concentration. We
simply add a trace element mixture like Ultra-Elements every week or two and that is it.
It is always best to start very slowing when adding trace elements and use half of what a
manufacturer recommends because the iron can cause hair algae to grow. Ultra-Elements is
also good Using things like ozone because it will removed trace elements(not really needed
in a reef). I will talk about ozone in another issue. I will also cover food for a Reef,
lighting, etc. in following issues. Remember to e-mail or send in your questions. We will
publish your questions and answers. Happy Reefing. Once you get going you will love it!
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