The Calcium Reactor - When To Decide If You Need One Or Not

There is a variety of equipment to assist in the maintenance of a marine aquarium. Some are essential such as the heater/thermostat, others are supportive for example the auto top-up system. The calcium reactor is often supportive, but in some circumstances it can be argued that it is essential.

First of all, what is a calcium reactor? This device is a means of getting calcium into the seawater. This is achieved by slowly moving the seawater through a calcium rich media in an acidic environment. The device is attached to two inputs, first seawater and second carbon dioxide. The seawater is as said fed into a media area where the gas is present. The gas is injected under careful control, usually a bubble count. The acidic environment created causes the media to dissolve and the seawater carries calcium into the aquarium. The flow rate is slow, counted in drips per second or similar.

The amount of calcium demand is the key to the usefulness and effectiveness of using a calcium reactor. There is a need to measure the calcium in the aquarium, so the only way to know is to test. Testing will let the aquarist know what calcium presence there is, but what needs to be replaced for that which is used? The answer lies in doing an ongoing weekly test as in this way the calcium demand of the aquarium can be ascertained. When the amount at the end of the period is subtracted from the amount at the beginning an indication of the demand is obtained.

If the aquarist is running a fish only aquarium then a calcium reactor is not required. If the system is a reef then the aquarium size has an effect.

A small aquarium will house a smaller reef which in turn will support less corals. So the calcium demand is going to be lower. It is more than likely that a soft coral reef will need little or even no supplementation as these corals have a low demand. A hard coral reef such as SPS will have a higher demand.

A large aquarium will obviously usually house a large reef with many more corals. In this case, though soft corals have a low demand for calcium, because of the number the need is going to be greater and supplementation may well be required. It is generally safe to state that a large reef with many hard corals such as SPS will need supplementation.

Having determined the amount of calcium loss over a week, the aquarist can now determine the best way of replacing it. There are two main ways, one is to use commercially produced supplements that are available in liquid or powder form or a calcium reactor. The choice will be determined by cost and convenience.

On the small reef, the soft coral one, the demand as said will be low. In this case it is likely to be financially sensible to use a commercially produced supplement. With the low demand the supplement is going to last for many uses and therefore will not be an excessively expensive option. If it is a hard coral reef the demand will be higher and the aquarist will need to consider how long a supplement package will last and the cost involved, and then make a decision about using a reactor.

The large reef if a soft coral one may still have a calcium demand that can be sensibly met by a purchased supplement. The hard coral reef however is going to need a much larger amount and so only perhaps three or four doses will be available for each commercial supplement purchase. This is going to prove expensive as time progresses.

Having done the tests the aquarist is aware of the calcium demand per week, so a decision can be made. For the large reef, certainly the hard coral type, it will be better to employ a calcium reactor. Even though routine seawater changes are done the calcium shortfall will not be made up and package supplementation will be expensive and impractical. For the smaller aquarium the aquarist may decide to employ a calcium reactor for the hard coral reef, even though package supplementation is an option, as the reactor is convenient and once purchased less expensive to use.

The lowest guideline for an SPS reef calcium level is 400 parts per million (ppm), but it is usual to maintain a level of around 420 to 450ppm. A little rise and fall in the level seems not to be a problem. This rise and fall will occur when weekly supplementation is employed using a commercial product, but is less or removed with the use of a reactor as the device is applied continually or more regularly.

It is important when using a commercial supplement or a reactor to follow the manufacturer’s instructions. The commercial supplement is straightforward but some initial additional attention to testing is needed with the reactor. How fast is the drip rate? The faster it is the more calcium is entering the aquarium. Adjustment should permit the calcium requirement to be met. Attention must also be given to the amount of gas entering the media chamber, this is usually indicated by a bubble rate.

Even though testing to establish the calcium demand has been done in the early weeks, the final demand cannot be discovered until the reef is fully stocked with corals. The ongoing demand will also vary to an extent. It is good husbandry to continue testing for the calcium level so that changes can be catered for.

Maintaining an acceptable calcium level will prove to be very worthwhile, the corals particularly hard types will benefit and also small reef life such as shrimps and snails.

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Tags: Aquarium Water, Calcium Reactor, Equipment, kalkwasser, water additives, Water Quality

How Do You Know When You May Need A Calcium Reactor?

A calcium reactor is a device which is used to provide much needed calcium as well as other elements dependant upon the media used. They work by slowly passing water through the media and recirculating it via a small pump. CO2 is slowly applied to the device to reduce the pH level in the device so that the media slowly dissolves. When the media dissolved calcium is released which is slowly passed into the aquarium system.

But how do you know if and when you will actually need one?

Well realistically it depends upon what you are keeping? If you are keeping a lot of hard corals then quite probably before long you will need to add one. If you dont keep hard corals then you may be able to control your calcium levels by water changes, additives, kalkwasser etc.

The best thing to do is actually test your water. If you find that you cannot maintain your calcium levels by performing water changes then perhaps you should try additives. If you find that you are having to spend a lot of money on additives then the next logical step would be either try kalkwasser or go straight for a calcium reactor.

If you decide to purchase a calcium reactor then there are loads available on the market plus there are quite a few desigs available now for those DIY enthusiasts.

There are some people who purchase a calcium reactor at the very start just because they believe that they need one.

I don’t agree with this as the only way to tell if you actually need on is either by your test kits or by the amount of money you are spending on other methods. If you are spending hundreds over the year then to be honest it is time to invest in a calcium reactor.

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Tags: Aquarium Maintenance, aquarium-additives, Calcium Reactor, Care, kalkwasser, Water Quality

Do You Need A Calcium Reactor When You Start Your Saltwater Aquarium

Over and over again I have said that research is imperative prior to starting your first home marine aquarium and I still stand by that it is and I am sure that lots of other people would agree with me.

However with research comes the belief that the costs may be higher than they actually need to be.

One of these such costs is the calcium reactor.

For some reason there is a belief amongst many people that a calcium reactor is required right from the offset.

A calcium reactor is a great device to install into the aquarium to ensure that the calcium requirements etc of the aquarium inhabitants are met and maintained.

But let’s face it at the very start of the aquarium live and potentially for a fair few months afterwards will there be enough life in the aquarium to require the purchase of a calcium reactor.

Don’t get me wrong I am a huge fan of the calcium reactor. It is a great device to use when the aquarium inhabitants needs cannot be met by additives and water changes but when the aquarium is first setup there is no life in there, therefore there is no pull on the calcium. A bit further down the road when the parameters are stabilising there may be a couple of fish in there and some corals but will the demand for calcium require the purchase and installation of a calcium reactor - probably not.

The best way in my opinion is to start off just with water changes and when your calcium water tests show that this is not maintaining calcium the additives should be used. Additives should continue to be used until such point that it would be cheaper to purchase a calcium reactor than continue purchase calcium additives.

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Tags: Calcium Reactor, Equipment, marine-aquarium, reef-tank, saltwater-aquarium

Magnesium - Why Is It Required In A Reef Tank

Magnesium is an element in the aquarium which is often neglected, however it is very important.

The topic of magnesium can be a very large and at times complex subject however in this short post I hope to provide only the information you need at present so you will know why magnesium is required and what levels you need to aim at maintaining it at. Read more

Tags: alkalinity, calcium, Calcium Reactor, Water Quality, water-parameters

Aquarium Additives and Hard Corals

The reef aquarium with hard corals ([tag-tec]SPS[/tag-tec]) is the desire of many an aquarist. The sight of pictures on the internet and in books only serves to increase that desire. With modern aquaria and equipment, plus the knowledge gained over recent years, this desire can be met, and more easily than some suspect.

It is taken as read that the need for high water quality is understood. High water quality means a proper and stable pH, between 8.0 and 8.4, nitrate less than 10 ppm (parts per million), phosphate preferably undetectable, but no more than 0.03 ppm, and ammonia and nitrite undetectable. Equipment should include a properly sized and efficient protein skimmer. Water movement, which I consider a part of [tag-tec]aquarium water quality[/tag-tec], should be vigorous and chaotic. There is also a need for strong lighting, the best of which is metal halide, supplemented by actinic T5 fluorescents. A greater number of T5 fluorescents can be used without a metal halide, as many as can be fitted into the aquarium including their reflectors. The T5’s should be an equal, or as near as possible equal, mix of marine white and actinic. However, at least in my opinion, the halide lighting is the best option.

If the reef is a mix of hard and soft corals, then parameters should be for the needs of hard corals. Soft corals will not suffer. Water quality measurements (pH, nitrate, phosphate etc) would be the same for both.

So that’s sorted then, back to additives.

Hard corals require calcium, and require it considerably more than the soft corals. Modern commercial salt mixes contain a good level of calcium, particularly those more recent ones which are specifically designed to give a high calcium reading for the [tag-tec]reef tank[/tag-tec]. The calcium level that should be maintained is 450 ppm, and should not be maintained at less than 400 ppm. (Some aquarists have the level at 480 ppm or sometimes a little higher.) This does not mean to say that the calcium reading must always remain exact at a particular level, it will of course vary to a reasonable extent. Even with regular routine water changes, a hard coral reef ’s demand will reduce it.

So how can calcium be maintained. The first option is supplementation with commercial products. The product instructions advise how much should be used to raise the calcium reading by X, according to the net gallonage of the aquarium. All increases should be gradual, and the instructions followed. These products are suitable for a small aquarium, for instance a nano system or up to a net fifty gallons or so. The products are not cheap, however, and larger aquariums will require larger doses so other methods need to be considered. The first, and recommended method, is to purchase a calcium reactor. This is an external device where the aquarium water is passed through the device, and is exposed to a chamber containing a calcium carbonate medium. This would normally have little effect. However, carbon dioxide is also fed into the chamber, and this causes the medium to slowly dissolve. As it dissolves it releases calcium, along with other trace elements. It is an efficient way of maintaining calcium. The water flow rate and the input of carbon dioxide must be correct and controlled. The aquarist must change the medium when it appears ‘mushy’ or is nearly gone. The calcium level must also be tested at least weekly as it is important to know that the reading is that desired. If too much calcium is being produced, then the running time of the device can be reduced until correct (ie. turned off for X hours each day). There are other means of introducing calcium, for example kalkwasser (limewater). Kalkwasser has drawbacks: it should really be mixed fresh each day which is a fussy procedure, and, as it has a high pH, needs to be introduced to the display aquarium slowly and carefully. The aquarist needs to exercise care as the mix is caustic. In addition, if the calcium level in the aquarium is low, the kalkwasser may be ineffective because the amount that can be introduced to the aquarium is limited. Put too much in and the sudden pH rise could be dangerous to the reef.

Talking of calcium brings the discussion to alkalinity. This is an important parameter and should be within certain readings. These reading are 9 to 11 dKH (151.1 to 196.9 mg/l). The alkalinity of seawater is its ability to resist downward changes in pH. It has a buffering capacity. Hard corals require stability and ensuring that alkalinity is at an acceptable level greatly assists this stability. Alkalinity affects the amount of calcium (and trace elements) that can be maintained. However, if alkalinity rises too high then calcium levels that can be maintained will be lower. So, as said, alkalinity should be maintained at a reading as suggested. How is the reading maintained? Again, commercial preparations are available which contain carbonates and bicarbonates. These should be mixed and applied as per the instructions supplied and according to the net gallonage of the aquarium. Again, the commercial preparations may prove to be too expensive for large reef systems. There is an alternative, applicable to small systems as well. Purchase some ordinary baking soda (sodium bicarbonate) from a shop. If this generates too much nervousness, obtain it from a chemist. It is safe but should be dosed carefully. As there will not be any instructions for use with a marine aquarium the following is a guideline: when raising alkalinity, divide the aquarium net gallonage by 25. Add a teaspoon for each 25 gallons. So 50 gallons would need two teaspoons. Aquariums with a net gallonage lower than 25 would need to add the appropriate fraction of a teaspoon. Mix the soda in some aquarium seawater and add to the sump, or to the aquarium away from livestock. That is the full daily dose, the alkalinity level should be checked by testing before adding any more on the following day. Once the required level is reached, the aquarist will soon discover how much his/her aquarium needs to be supplemented. For alkalinity and calcium, the following link gives further information. It really relates to those who are experiencing problems, but nevertheless gives information and parameter suggestions.

http://www.advancedaquarist.com/issues/nov2002/chem.htm

Iodine is considered by many to be beneficial to corals. This often refers to the soft variety, but there is a fairly strong body of opinion that suggests hard corals will benefit as well. Iodine in natural seawater has a very low presence, 0.06 ppm. Commercial preparations are available, and if used regard must be given to the net gallonage of the aquarium and the manufacturer’s instructions as usual. There is a drawback, and this is that, as far as I know, there isn’t a test kit that will reasonably accurately check iodine levels. If that remains the case, then do not exceed the recommended dose if the aquarist must use it. Alternatively, if regular routine water changes are completed and if the corals are healthy, expanded and growing, then don’t use it.

There are all sorts of trace element additives available to the aquarist. For example, strontium, molybdenum and iron. Other available magic bottles are said to contain a mix of essential elements. I am not a scientist. Nevertheless, the books I have read by very knowledgeable and up to date authors suggest that there is no scientifically supported need for these to be supplemented, therefore it must be that any benefit suggested from their use is anecdotal. I do not, and am not qualified, to challenge their use. However, I would suggest doing regular routine water changes using a high quality mix. There are several good preparations on the market nowadays. These will introduce trace elements to the aquarium seawater. Observation of the corals will advise the aquarist accurately: if the corals are expanded and healthy then.fine

Tags: alkalinity, Calcium Reactor, hard-coral.-aquarium-additive, saltwater-aquarium, sps-corals