Protect Your Livestock By Using Two Heaters

Whatever the size of the marine aquarium, it represents a fair financial investment. That’s just the system comprised of aquarium and support devices. Then there’s the livestock, which again requires a sizeable financial outlay. It is necessary to protect the livestock in as many ways as possible, first because it is life and second because it is costly.

One way of protecting livestock is by correct husbandry, keeping the seawater quality high, correct feeding and the like. The initial way to achieve this protection is to invest in adequate hardware in the design stage obtaining properly sized powerheads, protein skimmer etc. An important part of this hardware is the heater.

Aquarium heaters nowadays are generally reliable and can be accurate to about + or - 1.5 deg F or better. The unit comprises a heater that is at the lower end of the unit and a thermostat that is at the upper end. The more powerful the heater, that is the higher the wattage, the longer the unit will be.

The heater is best fitted in a sump if there is one as it could look out of place in the display aquarium though in a reef they are usually fairly easy to disguise. If they are disguised then there should not be any interference with seawater flow around them. They should be clear of the sand and preferably fitted at an angle, not vertically, though with modern seawater currents this is not quite so important.

The size of the heater should be calculated according to the total net gallonage of the system. This can simply be achieved by checking the recommendations of the manufacturer. It is usual to also size to the room the aquarium is in - if a cold room more heat is needed than in a warm one.

The heater as said is generally reliable nowadays but, like any piece of equipment, they can fail. They could fail in either the ‘off’ or ‘on’ position. This is a major failure: if a protein skimmer fails then there isn’t a nearly immediate threat to the livestock, though of course it needs attention as soon as possible. A heater failure needs immediate attention not just when convenient.

Dependant on the air temperature, cooling seawater does become such a threat if the aquarist doesn’t notice the problem. Seawater generally cools fairly slowly, the speed based on volume and air temperature. Seawater that is gaining in temperature quite quickly is a more serious threat. This is because if the heater has stuck in the ‘on’ position heat is constantly supplied and the seawater temperature rises continuously, more quickly than it would cool. As the temperature increases so the oxygen content decreases. Further, there is a general upper tolerance level for corals and fish, above which losses will occur.

The potential problem can be guarded against quite easily. When the total wattage required to heat the seawater has been calculated, divide it by two and buy two heaters. So if 200 watts is needed obtain two heaters at 100 watts each. The heaters are set to the same temperature and fitted parallel to each other. Some aquarists put one at each end of the display tank, but if a sump is available they can go in there.

“200 watts is needed so if one fails the aquarium won’t be heated properly.” That’s correct, but the immediate danger is removed. If one heater fails in the ‘off’ position, then the other heater will apply heat and attempt to reach the design temperature. If it can’t reach this temperature it will not switch off. This means that the seawater will not cool down as rapidly and the heater will at least be able to maintain a lower temperature. This means the aquarist has considerably more time to notice the problem before there is real trouble. When a replacement heater is fitted all is well.

If one of the heaters sticks in the ‘on’ position then there will not be a danger of overheating the seawater with the problems that will bring. The heater that is permanently on will obviously continuously heat the seawater. The other heater which is operating normally will reach the design temperature and switch off. The seawater is now likely to cool down though more slowly than usual. When the temperature drops sufficiently the second heater will switch back on again and so forth.

Using two heaters doesn’t cost more in electricity: the wattage is the same as if there were only one. However, the livestock are protected from excess stress or even disaster.

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Tags: Aquarium Heater, Aquarium Maintenance, Aquarium Water, Care, Equipment, Water Quality

It’s All Costing More

Nearly everyone is feeling the increase in cost, the cost of energy that is. Much of the world’s energy is derived from oil, and the price of oil is very noticeably going up. This is possibly going to continue for a longish period until some kind of equilibrium is achieved. The days of cheaper energy are probably gone forever.

In some oil producing areas output has been boosted to try and control the price increase. This isn’t going to have any immediate affect on cost, and if and when it does probably the cost of oil isn’t going to come down to its former level. Oil is becoming more scarce as well, and demand is rising.

So we are generally stuck with the cost - the motorist, the air passenger, the housewife and everyone else. This includes the marine aquarist.

The largest numbers of marine aquarists live in North America and Europe. Manufacturers of marine equipment, retailers and anyone else to do with the marine hobby, must be concerned. Marine aquariums are luxuries and, if things are bad enough (which I hope and believe they never will be) they will be one of the items that are not necessary and therefore represent a good saving if closed down.

Well before the need to close an aquarium down completely there are actions that can be taken to reduce energy use, with different levels of effectiveness.

The aquarium can be looked at in the same way as our homes - by using insulation the cost of heating them, or keeping them cool, can be reduced.

The first thing then, is to consider insulating the back and side panes of glass to reduce heat loss. This can be easily achieved by the use of polystyrene. This material is readily available and is best about 1 to 2″ thick. Cut it to size with any cut-outs done for pipes etc. It may be considered unsightly, so the inner surfaces of the polystyrene can be painted blue or whatever colour the aquarist prefers. I always think matt is better than gloss. The edges and outer surfaces can also be painted if wanted to match in better with the surroundings. If the tank has a back panel the polystyrene can usually be inserted between the glass and panel with a bit of adjustment, although not always. If not, put the polystyrene on the outside of the back panel. The polystyrene can be fixed in place with silicone glue, which secures it easily.

Talking of polystyrene, obviously a panel cannot be permanently fitted over the top of the aquarium as this would interfere with the lights a little! However, why not put polystyrene over the top of the aquarium after lights out and remove it before lights on? This doesn’t take any effort and only a few seconds, so isn’t going to interfere with the aquarists routine. With metal halide lighting it isn’t a problem as the light unit is usually well above the aquarium. If fluorescent lighting is in use then these lights are often nearer the water surface, but raising the tubes just enough to allow a polystyrene sheet to be inserted is usually possible and this should not be detrimental to the corals. Another advantage is that doing this will reduce evaporation. It is easy to stick the polystyrene to one or more glass or stiff acrylic sheets. Using glass or acrylic stiffeners for the top is not absolutely necessary as 1 to 2″ thick polystyrene is stiff anyway. This polystyrene can be painted too if required.

Remember that if there is a sump polystyrene sheets can be fixed to the vertical glass panes as well, and of course the top, though equipment in the sump may make this a little more awkward.

The aquarist should - over a period of some weeks - be able to note the reduction in electricity usage for heating the aquarium. It might be thought that lower wattage (W) heaters could be obtained. This is not necessary and would be wasting money, the heater(s) will come on as required but once the design temperature is reached they should stay off longer because of the insulation, which is where the saving is achieved.

With heating, also consider the temperature setting. If it is set at, say, 80 deg F, does it need to be? Could it not be turned down to 77 deg F? If reducing the temperature, do so slowly, not all at once. 1 deg a week should be fine.

For many aquarists, probably most, heating is the biggest user of electricity. There is another big user though, and that is lighting.

For a hard coral reef the current lighting used by most is metal halide. This lighting is very effective for the corals needs. However, it is usually high powered, that is to say the wattage (W) can be from 150 to 400. There are lower and higher wattages but these are probably the most frequently used.

Let’s say that a 250W metal halide bulb is in use. For every hour that it is ‘on’ it uses ¼ of a kilowatt (a kilowatt is 1000 watts). So if it runs for 12 hours then it will use 3 kilowatts per day. Over a week it will use 21 kilowatts, and so on. Most electricity suppliers charge per ‘kilowatt hour’, and the units are not cheap, and they certainly aren’t now! Many aquarists use lighting systems with multiple metal halide bulbs, so the cost also multiplies.

The first thing to consider is if the metal halide bulbs in use are too powerful for the depth of aquarium. If a 250W bulb is in use, would a 150W be sufficient?

Secondly, what is the lighting period in use? Are the bulbs running for 12 hours, or 11, or 9 maybe. Could the period be reduced? It is often said that 12 hours is a good lighting period for corals as that is more or less what they get in the wild. Well, yes, but it takes no account of the lighting power reduction in the morning and evening when light slants down through the water because the sun is not overhead.

Lighting periods can be reduced within reason. Many successful reef systems have 8 hours with the main lighting on. Actinic tubes may well be on for 8½ or 9 hours (coming on ¼ or ½ hour before the main lights and turning off after them).

If the aquarist wishes to reduce the lighting period, the exercise must take place over a considerable period, as the corals have become used to the lighting availability. Reduce the period by about 15 minutes every week until the target period is reached. The corals should not be adversely affected.

Another way of reducing the cost of lighting is to change the lighting system. Subject to the depth of the aquarium, many aquarists are successfully using fluorescent T5 tubes. Changing to these from metal halides is a big jump and needs to be done with care. It also entails a monetary cost - the tubes of course, but also the electronic ballasts. Soft corals can generally be kept under fluorescent tubes without problem, but light loving hard corals may need to be restricted to the upper third or half of the reef. Therefore it may mean redistributing some hard corals, and possibly changing others for soft corals.

For the aquarist who would like to reduce the cost of running his/her aquarium and at the same time is not too concerned about the cost of the change (how many aquarists are as lucky as that?) the relatively new LED lighting arrays could be of interest. They have several advantages including the running cost. They’re currently expensive.

Of course, there is an obvious way of reducing cost but probably not a very popular one. This is to reduce the size of the aquarium. If the new aquarium is not too deep then cheaper to run fluorescent tubes can be used, and it will not require so much heating. Many of the nano tanks are very popular and attractive, and some beautiful results are being achieved. There is also a reduction in the cost of routine water changes because of the smaller volume.

As said, the cost of energy has risen rapidly and what we were used to will probably never return. The aquarist can, to an extent, control the cost.

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Tags: Aquarium Heater, Aquarium Lighting, Aquarium Maintenance, Aquarium Water, Care, Equipment

Marine Aquarium Temperature

Aquarists keeping cold water systems very often employ chillers (coolers) to prevent the seawater warming up excessively. Warm water systems that are in naturally warm areas may well need to do the same to prevent overheating.

Whatever the warm water system, be it a fish only aquarium or a reef aquarium, the aquarium temperature needs to be kept stable, with only a small deviation from the design point. The majority of aquarists will employ heaters, and the rest chillers, or maybe both.

Modern heater units and chillers are reasonably accurate in maintaining temperature, usually with a deviation of between 0.5 to 1.5 deg F. Seawater is fairly slow to cool and warm, so these changes are acceptable. Wider changes in temperature can cause stress to livestock, the worst affected probably being corals.

On the wild reef seawater temperature is for the most part stable throughout the year. Average temperatures on these reefs are 82 deg F *. Note that this is an average, meaning that some are cooler and some warmer. It gives an idea of where the temperature in an aquarium could be set. Setting the temperature in the aquarium to 82 deg F will give a general average temperature approximation. So is that the temperature to use? As said the temperature is an average - there are variances between reefs and there will be differences at various depths.

The lowest temperature that should be used is more easy to state. Coral reefs (of the warm water kind) do not develop if the seawater temperature is 65 deg F or less. So the temperature must be higher than 65 deg F. However, this is too low for organisms to have a high enough metabolism and it is most likely they came from much warmer water, so they would decline rapidly and die. The lower water temperature acceptable is 75 deg F.

Some aquarists set a temperature at between 80 and 84 deg F. This is done because the metabolism of the whole aquarium is raised - fish, corals, shrimps and the tiny life forms in and on deep sand beds (DSB) etc. This increase in metabolism should mean faster growth. Fish will demand more food, this food will be digested and waste will be processed more quickly. So all should remain more or less in balance. Well, yes, it should. However, the aquarist is moving closer to the edge. The aquarium has a small gallonage no matter how large it is when compared to the sea. The water can heat more quickly. If the temperature is already maintained above 80 deg F, then it is a quicker journey to higher temperatures and potential trouble. What if a heater malfunctions in the ‘on’ position? What if metal halides are in use (the heaters will turn off but the water could continue to heat)? Additionally, seawater that is cold has more oxygen than warm seawater. As the temperature continues to rise oxygen continues to reduce. This could cause trouble in any system, but particularly in a heavily stocked fish only one.

In a well managed aquarium the oxygen question should not arise. A protein skimmer is no doubt in use. Also, adequate water circulation will provide efficient gas exchange maintaining oxygen levels. The point is, the potential for a problem is there.

Apart from potential problems with the example oxygen, maintaining higher temperatures is going to cost more in electricity, except for the aquarist who has to keep temperatures down with a chiller. This is, or should be, a secondary consideration of course, it is the welfare of the livestock that is being considered (and the aquarist: if livestock are healthy and vibrant then the aquarist will be happy).

So, what is the best temperature setting? Lower down, the livestock will have a slower metabolism and oxygen will be more plentiful. Higher, the opposite. It seems a compromise is in order. I would suggest a temperature setting of between 77 and 80 deg F. This is somewhere in the middle of the acceptable range and gives a reasonable safety margin should a heater malfunction etc.

I run a soft coral reef at a temperature of 77 deg F. The corals grow at a reasonable rate - they need cutting fairly regularly. The fish display good appetites, and the DSB has a high population of miniature life forms. I should mention that I have never experimented with higher temperatures - but then, why would I when all is well.

Whatever the temperature, it needs to be stable. Constantly changing the temperature setting will do no good at all. If the aquarist wishes to experiment with higher settings, then the temperature should be increased slowly over a considerable period. The same applies to temperature reduction of any amount. The aquarist who sets a high temperature needs to ensure the heater/stats in use are of high quality, and preferably there is an external heater control with an in-tank probe in use.

(* Reference: Aquarium Corals. Eric H. Borneman)

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Tags: aquarium, Aquarium Heater, aquarium-temperature, Equipment, saltwater-aquarium

Why You Should Use More Than One Heater In The Home Aquarium

As with anything in the [tag-tec]saltwater home aquarium[/tag-tec] hobby one of the areas which all aquarists must attempt to maintain is stability.

The aquarium temperature is one of these factors.

Allowing the temperature in the aquarium to fluctuate cause stress on the corals, fish etc which can bring out diseases etc or at worst even death.
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Tags: aquarium, Aquarium Heater, aquarium-temperature, Equipment, saltwater-aquarium

My Aquarium’s Too Warm!

In some areas of the world, including mine, it isn’t often that the words “isn’t it warm” can be heard. Often it is the pitter-patter of rain, or in the winter the howl of winds and the formation of snow drifts.

There are places in the world where it is always or mostly warm (coral reef areas are an obvious example). In the summer the weather can be warm and very pleasant where I live. Well, no problem with that says I! It can be a problem, though, if you keep a [tag-ice]salt water aquarium[/tag-ice].

A tropical salt water aquarium is designed to run at a given temperature, usually between 75 and 80 deg F. This temperature is maintained by heaters. Here’s the scenario - the summer has come with its increased temperatures, so the heaters are not working anywhere near as hard, sometimes not at all. The equipment on the aquarium hasn’t changed, so there is heat going into the water from pumps and power heads, and in addition the water is being warmed by the lighting. Even fluorescent tubes have this effect, but nowhere near the effect that halides have. In addition, a few aquarists have glass covers on their tanks to reduce evaporation and/or prevent inmates jumping out. So the sum total is seawater that is at a temperature above the design temperature. A little above is not too bad, but the temperature can rise too much. This causes reduced oxygen, and the heat can stress the tolerance of corals and other livestock. So we don’t want that.

Right, we could remove cover glasses, and use fans etc to help control the seawater temperature. Some methods work fairly well.

Consider how often the [tag-tec]aquarium temperature[/tag-tec] is likely to rise above the design temperature. This is fairly easy, the weather patterns (temperatures) are known to you. If the period of likely excessive temperature is considerable, consider purchasing a chiller. Remember that when a chiller is operating, the heaters will not be, so electricity usage shouldn’t be increased by the chiller.

A chiller is a device specifically designed to cool seawater temperature. The devices I am talking about are not modified beer chillers etc, but equipment specifically designed to cool overheating aquarium seawater. The contact areas between the equipment and the seawater are of special materials, so the seawater will not be adversely affected.

An [tag-tec]aquarium chiller[/tag-tec] is not for everyone, as they are expensive and fairly heavy on electricity. So there needs to be a good case, that is, the knowledge that they will be reasonably extensively used, before a purchase is made.

They are easy to obtain and come with clear instructions. Be sure that the chiller has the capacity to deal with the net gallonage in your aquarium. When connecting to your system, be sure to adhere to the seawater flow rate recommended by the manufacturer, so the seawater has time to cool. The usual case is that the heaters are set to the design temperature, and the chiller thermostat is set to 2 or 3 deg F above the design temperature. The seawater heats up, the heaters stop heating, the chiller thermostat detects the heat rise and, well, yes, the chiller starts chilling.

So there we are. Overheating problem solved.

Tags: Aquarium Heater, aquarium-cooling, aquarium-equipment-marine, aquarium-heating