Pure Inspiration for Marine Hobbyists
By Richard Aspinall
Pictures: R. Aspinall
There are a number of methods to keep up the degrees of calcium, alkalinity and magnesium inside our techniques. The ‘Big 3’ as they’re typically identified, are the parameters that we have to monitor most carefully and preserve with the minimal variation, if our corals and plenty of different calcium-using animals are to develop and prosper.
Direct dosing utilizing pre-mixed liquids, Balling techniques and Kalkwasser stirrers are employed by many with the latter falling out of favour considerably in recent times. Balling strategies are more and more frequent in Europe, although from what I’ve learn, calcium reactors nonetheless maintain sway within the US.
So what are these strategies attempting to realize? In essence we have to replenish the chemical parts within the water that the expansion processes of onerous corals, clams and different inverts together with calcareous algae are eradicating from the tank water as they lay down their very own skeletons, shells and so forth. Within the oceans a spread of geological processes ‘tops up’ the chemical steadiness together with run-off from eroding rocks on land. In a closed system like an aquarium the hobbyists must take motion.
Calcium reactors are very easy in precept. Lifeless coral skeletons (calcium carbonate within the type of aragonite), crushed into small items, are dissolved and the weather and chemical substances they comprise are launched into the aquarium water and can be found for uptake by the aquarium inhabitants to make new skeletons. Pretty easy in idea: because the coral gravel dissolves it releases parts within the appropriate proportions. In precept, if the alkalinity of the water within the aquarium operating a calcium reactor is throughout the normal 7-10dkH vary then the ensuing calcium and magnesium ranges ought to be appropriate additionally (in observe that is hardly ever the case – see the troubleshooting part). A calcium reactor gives a balanced addition of calcium and carbonates (that contribute to alkalinity), one can’t alter one parameter with out altering the opposite. Nonetheless, techniques with very prolific coral progress might require further inputs of calcium, in truth I’ve visited a number of techniques that us a kalkwasser stirrer in addition to a calcium reactor to supply sufficient calcium. As with something on this passion, there’s all the time extra to study after the fundamentals!
How does a calcium reactor dissolve the coral media?
Once more, that is easy in precept, a small quantity of carbon dioxide is drawn into the reactor vessel, by way of valves to regulate the circulate. The CO2 dissolves within the water contained in the reactor to supply a weak acid, which dissolves the coral skeletons. As water is repeatedly operating into the reactor from after which into the aquarium, the water exiting the reactor (effluent) returns to the tank richer in dissolved parts. Usefully additionally it is richer in sure hint parts that the lifeless corals took up of their lifetimes as properly.
In observe we will tune the pH of the calcium reactor by controlling the addition of CO2, extra CO2 means decrease pH and fewer, a better worth. To do that a pH controller is crucial. A pH probe is fitted into the reactor and the controller set to generate a pH within the reactor of round 6.5. If the pH falls beneath this stage the controller shuts off the CO2 circulate utilizing a solenoid operated valve on the CO2 supply bottle and when the worth begins to rise the solenoid valve is opened as soon as extra. pH controllers are usually not all the time used, however I might think about one a worthy funding to make sure the acidity stage within the reactor is stored low sufficient to dissolve the media but additionally not too low as to adversely cut back the pH worth in the primary tank.
Let’s have a look at the equipment…
CO2 bottle and regulator
Right here we see the regulator/valve/solenoid meeting. When powered the solenoid has a small indicator mild. The needle valve is higher left.
CO2 is a colourless, odourless gasoline that when mixed with water types carbonic acid. It’s the identical stuff that erodes outdated statues and creates limestone caves. For our functions CO2 is supplied in small pressurised cylinders which are typically single-use. Hobbyists with massive techniques typically discover that they obtain higher general financial system through the use of massive industrial cylinders which they’ll get refilled.
The CO2 circulate is regulated by a valve with two gauges, one tells us the bottle stress and the opposite the working stress. A regulator contained in the valve retains the working stress at appropriate stage as the general cylinder stress drops, which is crucial to keep away from over or below dosing.
Hooked up to the primary valve/regulator is a solenoid managed valve which requires a mains plug connection. It is a security function which means if the facility fails the solenoid shuts the valve and the CO2 is contained. Its different use is with a pH controller permitting the CO2 circulate to be turned on and off as required and as famous above. Hooked up to the solenoid is a needle valve for fantastic management of the CO2 output. In observe needle valves might be tough to set good so I want to make use of an additional in-line air valve for fantastic tweaking. A one-way valve hooked up into the CO2 feed line is a good suggestion additionally.
I’m utilizing TMC gear for this text and I’m grateful to TMC for sending it over, however please word that no matter regulator, CO2 supply and solenoid your use, all of them work in the identical fundamental means. Although in case you’re shopping for this equipment in a UK fish store, the possibilities are you could be shopping for TMC gear.
The Reactor – “calcium reactor”
This compact design of reactor is totally different to many bigger fashions. The left hand enter takes CO2 and the pH probe might be seen fitted into holder within the centre of the highest plate. To the correct is the influx feed. On this mannequin the circulation pump is at decrease proper and in case you look fastidiously you’ll see the CO2 influx pipe operating down and right into a chamber on the very backside left.
Calcium reactors fluctuate enormously of their design, ease of use and sturdiness and naturally worth. Additionally they are available in varied sizes and must be chosen in line with the wants of your tank, now and sooner or later, when it’s filled with Acroporids and Tridacnid clams rising like loopy (hopefully).
The reactor is stuffed to the really helpful stage with the media after which hooked up to a supply pump. This may be accomplished by taking a feed from an current return pump, for instance, by inserting a T junction into the pipe, with a reducer sufficiently small outlet to permit airline tubing to be fitted that then attaches to the reactor inlet. A greater answer makes use of a devoted peristaltic pump that gives the small quantity of normal circulate wanted. Peri pumps may produce a good stress to pressure water into the system.
Some compact reactors corresponding to this mannequin – which TMC say is their greatest vendor on the moment- are designed to work with no devoted feed and use their inside circulation pump to attract in aquarium water. Water within the reactor chamber is circulated by a pump which additionally serves to completely combine the CO2 into the water because it passes by way of it.
Bubble counters are important, they help you see what number of bubbles of CO2 are coming into the reactor over a given time frame. Many models have exterior bubble counters, although this reactor has a barely more durable to see counter built-in to save lots of area. Equally, one other chamber exhibits us how a lot water (in drops) is coming into the unit, with a valve on the output permitting us to regulate this setting as properly. Not all reactors have this function and simply depend on you counting the drops out. Exterior bubble counters are greatest stuffed with RO water and never aquarium water – because the liquid evaporates they’ll turn out to be clogged if salt water is used.
In essence we’ve all we want. Circulated water, managed CO2 enter and a managed water output.
The pH Controller
This useful piece of equipment takes numerous hassle out of operating a calcium reactor. As soon as calibrated, the probe is inserted into the reactor (most reactors can accommodate a probe these days) the place it screens the pH of the water within the reactor. A worth of 6.5 is really helpful to dissolve the media with ease.
The controller is about to ‘come on’ and activate its energy socket to open the solenoid valve when a worth of say 6.9 is reached and switch off when the pH reaches 6.5. On this method the reactor will all the time be on the proper pH and if and if you modify the circulate charges the reactors pH will stay appropriate.
Utilizing a pH controller means which you can keep away from the tedious checking of the effluent pH and permit the controller to do the give you the results you want. You’ll need to set the controller to the higher and decrease values, most are very simple to regulate and set.
Organising
That is how I do it, however everybody has their very own methodology.
It’s a good suggestion to file the modifications and word the tendencies and verify repeatedly over time particularly because the media runs low or coral progress will increase.