DIY Metal Halide Lighting

Do It Yourself (DIY) with a project of any kind is not for everybody. However, there are large numbers of people who do complete various projects successfully, and there is a lot of satisfaction to be had never mind the financial saving. Often the only requirement to start a project is a guide or laid out plan of action.

Marine aquarists have a lot of scope to demonstrate their skills with DIY. For example, some construct their own filters, protein skimmers, lighting hoods and aquarium stands etc. Some make the aquarium itself.

The lighting for a reef aquarium is very important for the health of the corals. Failure to provide proper lighting, both intensity and spectrum, is the road to failure. Different coral groups require different intensities of light. Where the aquarist requires intense light then metal halide systems are often chosen.

The aquarist could consider DIY for the metal halide system. There isn’t a requirement to be a qualified tradesman, just a need for a basic capability and the care to complete the job. With electrical items of course the aquarist needs to be aware that electricity and misuse are dangerous. Having said that, there isn’t any reason why a DIY project cannot be completed in this area also. However, if there is doubt, don’t attempt it. If the job is in progress and there is doubt, obtain qualified advice.

As already said, all the DIY aquarist really needs is the guideline and advice to follow. So below is a link which provides that. Using a search engine on the internet will no doubt find more sources.

There is another way for a DIY project to commence, though this one is even easier because the parts don’t have to be searched for. This method is called ‘retrofit’ and there are kits available that provide all the parts and the instructions for construction. They are very straightforward.

Before the aquarist starts it is necessary to research the intensity of lighting that is required, that is the power (watts shown by a ‘W’) of the bulb(s). This intensity depends on the type of corals to be kept and also the depth of the aquarium. This applies whether the lighting is a DIY project, a ‘retrofit’ kit, or ‘off the shelf.’

http://www.personal.psu.edu/sbj4/aquarium/mh/mhlighting.html

---

If you're new here, you may want to subscribe to our RSS feed. Thanks for visiting!

Tags: aquarium, Aquarium Lighting, Aquarium Maintenance, Care, DIY, Equipment

Will LED Lighting Ever Replace Metal Halide?

Whatever type of marine system is kept lighting is important. With a fish only aquarium the fish need a day cycle and of course need to see where they are going. It’s also good that the aquarist can see the fish! With reef systems the lighting is also important for the same reasons as far as the fish are concerned and more important for the corals.

Before looking at LED’s (light emitting diodes) it’s necessary to see what the LED’s need to be able to do to compete with metal halides.

Metal halide lighting systems are used exclusively for reef aquariums (if used on a fish only system then electricity is being wasted). Sometimes the aquarist is able to use fluorescent T5 tubes, but this depends on the depth of the aquarium - can the light penetrate deep enough?

In this case it is assumed that metal halide bulb(s) are needed.

Metal halide is basically a bulb that uses a filament, the bulb being inside a reflector. The bulbs are rated in watts and there is a range available, the most usual ones being from 150W up to 400W. The wattage is chosen according to the depth of the aquarium. The more watts, the more expensive it will be to run because of electricity usage.

The length of aquarium that a single bulb can light with usual width aquariums is 3ft (circa 91.5cm). This is a guideline not a rule. For a 6ft aquarium two bulbs would therefore be required, doubling the running cost.

The bulbs also need to meet another demand of the corals in addition to intensity and that is spectrum. A lot of the commonly kept corals contain zooxanthellae within the flesh. Zooxanthellae are single celled algae that are essential to the well being of the coral. In order to function (photosynthesize) they need light of the correct wavelength and fortunately metal halide bulbs can achieve this light output. In fact, there is a choice of outputs within limits.

Metal halide bulbs need to be changed regularly according to the manufacturer’s recommendations or the intensity could diminish and/or the spectrum shift.

To make the reef more natural (a goal which is being achieved more and more), many if not most aquarists incorporate one or two additional fluorescent tubes which are usually in the blue spectrum. This assists the delivery of the correct light to the corals and additionally, with the use of electric timers, gives a ‘dawn and dusk’ effect. That is, the blue fluorescent tubes switch on around half an hour before the metal halide, and switch off around half an hour after the metal halide. This avoids sudden bright light or sudden darkness, both of which are undesirable.

Are there any downsides to metal halides? Yes, there are two. The first one is running cost because the bulbs are electricity hungry. Consider a bank of two 400W bulbs ‘that’s not far away from a kilowatt per hour. If the lights are on between 8 and 11 hours a day’..well, you get the idea.

The second downside concerns the aquarium livestock. Stability in any marine system is very important and should be maintained as far as possible. Metal halide bulbs run very hot, and radiate directly into the aquarium as obviously they must. This heats the seawater and it is possible for the seawater temperature to rise unacceptably. If this is the case then the aquarist needs to purchase a chiller (seawater cooler) which is not particularly cheap to purchase or cheap to run. It may be possible for the aquarist to run surface air fans for cooling and many aquarists do this. In this case ideally the seawater temperature and/or time need to be linked into the fan system or, if the seawater cools down because the metal halide has turned off, it may be overcooled and the heaters will switch on for longer periods using more electricity.

So then, what about LED’s? These type lights are used widely nowadays for decorative and commercial purposes as well as more recently being of use to marine aquarists. Aquarists could already be making use of low-powered LED lighting in the form of blue lights that switch on after all the other lights have switched off. They simulate moonlight and give a really good effect, beams of flickering weak light in the seawater. These are not a competitor to metal halides of course.

Fairly recently more powerful LED’s have appeared. They are similar to metal halides in two ways - they come in a canopy and use electricity.

The makers of some canopies have claimed that the light output (the combined output of all the LED’s in the canopy) is equal to X watts of a metal halide, this being 150W, 250W or whatever - the more LED’s the more power. I am not a lighting expert but have noted some argument over this claim. However, contributors to the argument seem to agree that the output is close and is increasing as technology advances. The important point is that there are reef systems that are thriving under LED lighting.

There is another LED system available that is not a standard canopy. These resemble to an extent a fluorescent tube in shape, and can be purchased in different lengths and, again to an extent, different spectrum outputs. So, as with fluorescent tubes, different units can be combined over the aquarium.

LED’s do not need to be changed as regularly as metal halides, in fact they could last 20000 hours. That’s a long period of aquarium lighting, just divide it by the amount of time the aquarium lights are on each day. So there isn’t a requirement to spend money on new bulbs once a year or so.

The heat from LED’s in canopies is not directed into the aquarium as the canopies usually contain a fan to channel the heat away. In warm areas this will add to the work that air conditioning needs to do. Most aquarists will not need to purchase a chiller or employ fans to cool the seawater, which should remain more stable in temperature. The LED’s that are a little reminiscent of fluorescent tubes do not have fans - to be honest I am not sure of the heat output effect but would assume that it will not be great as each ‘tube’ often has less than ten LED’s present.

There isn’t a requirement for additional fluorescent tubes, so the aquarist misses that expense and the need to change the tubes once a year or less. This is because the LED’s incorporate both white and blue LED’s and, in the canopies at least, these usually can be timed on and off according to the aquarist’s wishes. In fact, in the more expensive canopies, the effect of a cloud rolling across the sky can be timed in.

Obtaining a metal halide system costs less than an equivalent LED canopy, and obtaining a fluorescent tube costs less than an LED ‘tube’. That is the problem at the moment with LED systems, the initial cost.

However, when the ongoing cost of a metal halide is considered against the same for LED’s, the LED’s show a considerable saving. In addition, the LED’s do not heat the seawater (at least not to the same extent) and permit the aquarist to maintain temperature stability more cheaply.

Importantly, LED’s are not so electricity hungry.

LED technology continues to move forward and it seems clear that if the current LED systems can be successful then ones in the future will be and better. It is now necessary more than in earlier days to be careful with electricity costs and it is doubtful if this is going to change significantly.

My own guess is that the future for LED’s is assured and the metal halide will begin to fade away before too long. The price of LED systems does need to come down though before LED’s become the usual lighting system considered by most reef aquarists.

---

Tags: aquarium, Aquarium Lighting, Aquarium Maintenance, Care, Equipment, metal-halide

The Porcelain Crab

Crabs can be helpful or not in the aquarium. Some of the larger crabs are not required as they blunder about causing damage and disruption. Others¸ such as some of the hermit crabs, are colourful, interesting and at the same time perform a useful job scavenging which assists in keeping the system clean.

Another interesting crab is the porcelain. This term is often thought to refer to one crab but this is incorrect, they are multiple. Their size is not a problem as they achieve around ¾” to 1¼”. There’s another two good reasons besides their size which makes them particularly interesting to marine aquarists. First, they are very colourful. Second, they usually reside in the tentacles of an anemone, or more unlikely down underneath it. So they are similar in that respect to clownfish.

Porcelain crabs come under various common names depending on which one it is. To take one in particular the common name is ‘dotted anemone crab’, or sometimes the general ‘porcelain crab’. The proper name is a tongue twisting Neopetrolisthes ohshimai.

http://www.geodia.com/gallery2/main.php?g2_view=keyalbum.KeywordAlbum&g2_keyword=crab&g2_itemId=132

They are best kept in a reef system, obviously with an anemone. Anemones such as those inhabited by clownfish are appropriate. Though one or two of this type of crab are able to defend their home against clownfish, this one is likely to lose out and it is best if the aquarist makes the choice - clownfish or crab. They are both suitable for inclusion with an anemone. It is best that one crab is kept as two of the same sex will fight.* If it is known that two are a pair then fine.

In a high quality habitat they are hardy, but it would be best for the aquarist to gain experience and feel confident about aquarium general maintenance including seawater quality before proceeding. This is not so much for the sake of the crab - experience is required for the sake of the anemone as, at least in my opinion, though I note quite a few others of experience agree, an anemone is not the ideal starter for a beginner. If an anemone and crab are to be kept, it should be remembered that the anemone requires the proper lighting, though this is likely to be present in a coral reef aquarium.

Feeding the crab is not difficult. The crab is a filter feeder and to facilitate this method the crab is able to spread hair-like fan structures into the seawater. So to feed them the aquarist could target liquidized filter type foods over them. This needn’t worry aquarists however, as the crabs will also take small pieces of de-frosted food such as lance fish, shrimp etc. The crab will not require much food though feeding should be fairly regular, and any extra food the crab ignores will probably be caught by the anemone, which in turn requires feeding with the same kind of food in larger pieces but less often.

When considering livestock for an anemone, clownfish of various types are probably the choice of most aquarists. If a crab such as that described is chosen then the interest is just as high and the sight of the two life forms co-existing just as fascinating.

(*Ref: Marine Atlas. Helmut Debelius & Hans A Baensch)

---

Tags: aquarium, aquarium-livestock, Care, Equipment, Invertebrates, reef-tank

The White Spot Hermit Crab

Crabs are not always welcome in the marine aquarium. Some of them could cause trouble, either blundering about and knocking things over, possibly interfering directly with corals or just growing too large.

There are some crabs however that often find favour with aquarists, and these are the hermits. They are quite comical as they wander about the aquarium, and at the same time are useful as scavengers. They can be colourful too, though this is usually the legs as this is the part that can be seen. The shell is not the crab’s own; it has been found empty or taken over from a snail for example. The crab keeps itself secure in its shell with a tenacious grip. If excessive force is used to remove the crab, then the grip will not be broken, but the crab’s body will break apart. The grip is so strong because remaining in the shell means survival, outside of it means death as the crab is highly vulnerable. The crab holds itself inside the shell with its rear pair of legs which slant forward to increase strength, and in addition the abdomen is shaped to fit the shell reasonably.

This is one danger from the hermit crabs, their need for a shell. I once had a large snail and a hermit crab in the same 4ft aquarium and for a while all went well. However, the hermit began following the snail about, trying to get at its flesh and generally upset it. Eventually it damaged the snail which died. The hermit crab was next seen in the snail’s shell. Though I couldn’t be sure, I wondered if I was at fault, perhaps the hermit had grown and needed a larger home. I would suggest that a small selection of suitable shells is left in the aquarium, so that hermit crabs can change home if they have a need.

There are several suitable hermit crabs for the aquarium, and provided there are no dangers present (such as for example puffer fish) a fish only system could be used, though there needs to be rocky structures present. The best habitat however is a reef system, where the crab can find security and its ‘cleaning’ activities are perhaps the most useful.

The hermit crab being focused on here is commonly called the white spot hermit crab, or the scarlet hermit crab, or the knobby hermit crab. There may be more common names demonstrating that for identification purposes the proper name is the best. In this case the proper name is Dardanus megistos.

http://decapoda.free.fr/illustration.php?n=5&sp=225

It is necessary with this crab for the reef to be securely built, though this generally applies to all hermits, particularly the larger ones. They are not particularly naturally destructive, but just clumsy. They could grow to around 4″ (circa 10cm) including and dependant on the shell they inhabit. Only one should really be kept or it is likely fights will occur. It is also necessary to exclude shrimps in general as the crab could eat them. The hermit crab should be seen during the ‘lights-on’ period but is also active at night. They are hardy in a good habitat.

Feeding is simple as the hermit crab appears forever hungry, constantly looking for food. They will take de-frozen lance fish, mussel flesh, crab meat, and almost anything else that is edible. Hence they are fairly good at cleaning up.

This particular hermit crab is not suitable for a small aquarium; one of around 4ft (circa 122cm) should be fine. Though the crab population should be restricted to one, an aquarium of this size affords space for other inhabitants to spread interest.

This is one species of hermit crab which is interesting and colourful. However, if the aquarist wishes to keep more than one, or keep one in a smaller aquarium, there are types that could be available. For example, there is the red reef hermit crab, proper name Paguristes cadenati. This could grow to around 1½” (circa 4cm). A trip to the local fish shop (LFS) is likely to turn up hermit crabs that are suitable for the aquarist’s particular system.

With proper attention to the habitat and some to other livestock, the hermit crabs are as said useful, interesting, amusing and hardy. Additionally they pose no problems with feeding. All they require is a new home occasionally.

---

Tags: aquarium, Aquarium Maintenance, aquarium-livestock, Care, invertebrate, reef-tank

An Aiptasia Predator

Marine aquarists, generally, have all the pleasure and little grief, with high seawater quality and a happy mix of livestock. True, on occasion there can be some trouble - with algae for example, but generally it’s a peaceful and pleasurable hobby. It is with me.

There is one thing wrong though, which doesn’t really harm the pleasure but is irritating nevertheless. There is an ongoing battle with the aiptasia anemone and this is happening in many aquariums, particularly reefs. I control the little blighters with Joe’s Juice, a commercial application that kills the anemone it is applied to. There are other commercial formulations available. Unfortunately, as I understand it, when the anemone is attacked it releases emergency spores, so though the parent is doomed the babies are going to grow for the next round. In addition, in a reef system there are many caves and crevices and all the aiptasia cannot be eliminated.

There are natural controls such as the copperband butterfly fish (Chelmon rostratus). This fish is a beauty in itself and is recommended by some respected authorities. However, not all aquarium systems are suitable and the fish is not suitable to a beginner.

There is another predator that is hitting the headlines, and it is a nudibranch. These creatures are like snails without a shell. Some of them are really lovely and others not. The one of interest here is fairly small and quite good looking. Its proper name is Berghia verrucicornis.

The natural diet of the nudibranch is aiptasia. They are otherwise reef safe and could breed in the aquarium, all conditions being acceptable. They are sociable with each other so more than one can be kept. What a discovery! Aiptasia, the writing is on the wall!

These little creatures are already being commercially bred and can be purchased for home delivery. Unfortunately, as far as I can tell European aquarists may have to wait a while for supplies to materialize. Aquarists in the United States are more fortunate as they are currently available.

The nudibranchs need to be acclimatized carefully and information is provided about this. Once settled they are reported to be hardy.

It is of course important that there isn’t anything in the aquarium which will harm the nudibranchs and checks will need to be made.

There are two links following that are concerned with the nudibranch. Anyone wishing to find out more has only to go into Google and type in the nudibranch’s proper name and further links will be found.

http://reefkeeping.com/issues/2004-01/ac/feature/index.php

http://www.berghia.net/

---

Tags: aiptasia, Aquarium Maintenance, aquarium-pests, Care, Equipment, reef-tank

This Wonderful Hobby

The marine reef aquarium gives the opportunity for aquarists to own and view something special. In the world of hobbies this must rate near the top if not at the top. Photography is an embracing hobby to its devotees, but produces copies of the real thing even if done artistically.

The captive reef is something else. For a start it is the real thing. I can hear some say ‘but it isn’t a real reef, they’re in the sea’. Correct, wild reefs are in the sea, but the captive reef is the real thing, a living multi-organism, accepting that the life forms present are not so diverse. It is a world in an aquarium, with Mother Nature the main architect and the aquarist her accomplice.

Accepting the restricted space available on the captive reef the aquarist can choose from so many different life species. There are fish of course, in different shapes and colours. Some may be algae eaters, some plankton eaters, some omnivores. With a little care the mix of colours and shapes is amazing. Some of the fish may be open water swimmers, some rock ‘sitters’, others take an anemone as home. Now there’s something amazing, fish living in an anemone safe from the stingers and protected by the same.

The word ‘reef’ conjures up thoughts not only of colourful fish but of corals. Once again there is a choice of type; some may choose soft corals and others hard types. Soft corals with their lovely pastel colours, the taller ones swaying in the seawater currents as the fish flit between them. Hard corals that are more mentally linked with the words ‘coral reef’, some with short thick branches, others with long ones depending on the area of the wild reef they would naturally inhabit. Clustered on the captive reef they look magnificent.

Not even mentioning some coral types that could be kept it goes on: hermit crabs wobbling along on their way, always looking for something to eat, comical and colourful, snails smoothly cruising, some with their snorkels extended, and both hermits and snails supplying entertainment and interest to the observer. Maybe there are some shrimps to be seen, their long white antennae waving.

If there is an anemone it could well have fish nestling in its tentacles as mentioned. If not, look closer; is there a tiny crab, beautiful patterns on its shell, nestling among the tentacles? There could be.

Look closely at the rocks, above and where possible below, there could be tiny fanworms to be seen, ready to shoot back into their small tubes. There could be much larger fanworms to be seen with their larger tubes standing out from the rocks, and their magnificent fan ‘heads’ on display gathering food. There may be growths of algae, perhaps of red or green or brown.

Look at the sand bed closely. There may be thin white worms waving up into the seawater and sweeping the area around them for food. Particularly after dark tiny crustaceans could be seen scurrying about on their urgent errands, if the aquarium is aged there could be hundreds. Plus there could be strange worms with bristles and other alien looking creatures.

It doesn’t end there - there is more life yet. Consider the colours on the insides of the aquarium, particularly the back. Where permitted encrusting algae grows with colours of pink, red, green and many hues of brown. Very natural and very wanted.

Sit and watch. The fish swim about as they would on the wild reef, wary but ready for that next morsel. The corals are extended and beautiful. All of this feeds the aquarist peace. As the lighting steps down towards ‘sunset’, the fish prepare for the night, moving closer to their night quarters and then disappearing into them. After dark, some corals close down to await the next day. With fish gone the night shift appears, these being the majority of the tiny crustaceans already mentioned. They are so busy, everything is so urgent. With the return of light, as the lighting steps up with ‘dawn’, the day shift starts to re-appear and the tiny nightlife once more hides.

Are we reef aquarists just lucky? Well, no, we’ve had a few ups and downs and spent some money. We’ve researched and done everything possible to ensure our charges are healthy and safe. We change some seawater regularly, test the seawater for quality, ensure lighting is adequate, check the support equipment, enjoy feeding the reef inhabitants and the like. So we’ve done and do our bit to assist Mother Nature, and it works.

But then again, are we lucky? Well, yes, we are.

---

Tags: aquarium hobby, aquarium-fish, Coral Reef, fish-tank, home-aquarium, saltwater-aquarium

The Dancing Shrimp

There are a few shrimps which find favour with aquarists; some of them have been the subject of other texts on this website. This is another favourite, both for its colouring and character.

Before starting, a picture is needed:

http://fr.reeflex.net/tiere/1019_Rhynchocinetes_uritai.htm

This shrimp comes under a few common names which could lead to confusion: dancing shrimp, rosy dancing shrimp, camel back shrimp and common dancing shrimp being some of them. The proper name is Rhynchocinetes uritai.

They’re lovely to look at and one of the common names - ‘camel back shrimp’ - refers to the clear hump on the back. Another common name - ‘dancing shrimp’ - refers to the jerky way in which they move.

The shrimp is social and can be kept in a group. They do not usually have any trouble with other commonly kept shrimp except perhaps the boxing shrimps, Stenopus sp. Obviously the number kept depends on the size of the aquarium - two could be kept in a relatively small system.

The best habitat for the shrimp is a reef aquarium as this affords all the crevices and caves that are needed. There shouldn’t be any other livestock that could threaten the shrimp of course. Keeping the shrimp in a reef aquarium does have a potential drawback though, and that is the shrimp could ‘have a go’ at soft corals, including colonial anemones. Then again, many aquarists do not have this problem. Hard coral types are usually left alone.

There is another possible advantage to having these shrimps. Please note the word ‘possible’. This concerns that unloved nuisance of many aquarists aiptasia. These anemones are often introduced on the rock of a new coral, or with live rock. After a time during which the anemones spread, an ongoing battle usually takes place between the aquarist and the anemones. This battle usually ends with the aquarist being in control generally but having to periodically re-attack. An uneasy truce could describe it. There have been anecdotal reports on the internet that these shrimps attack aiptasia, mainly young ones. It has also been reported just as often (to my knowledge) that the shrimp ignore the anemones! I haven’t seen any reports following controlled experiments. Perhaps they will, perhaps they won’t.

Generally the shrimps are more timid than other commonly kept types and avoid the bright light of a reef system, initially anyway. They should settle down and be seen more often, though they usually retain their preference for dimmer light. It is more unlikely that they will rise to take food so the aquarist may have to target feed the shrimp. This is not difficult, not least because they will take the usual fare such as de-frozen lance fish, mussel etc. They may well chase brine and mysis shrimp that have been released as food.

As with other shrimps they will shed their exoskeleton from time to time. This is to permit growth. A new exoskeleton will harden over a fairly short period and the old one looks like a shrimp albeit a dead one.

All shrimps need careful acclimatization to the new home aquarium and it is reported that this one is perhaps more sensitive. Therefore transfer to the new seawater should be completed with care. Empty out half of the seawater in the transport container. Then, using an air tube and air tube clamp, drip aquarium seawater into the container until it reaches the previous level. The drip rate is a little short of a slow continuous trickle. It is probably worthwhile carrying out this procedure twice. When the shrimp is introduced to the aquarium it must not be exposed to air. It is also worthwhile switching off the main lights for a day - this period will not harm any corals.

The dancing shrimp in the proper habitat is a delight. They will probably not be seen as often as other types. For those aquarists who battle the troublesome aiptasia wouldn’t it be great if all the anemones disappeared. No guarantee though.

---

Tags: aquarium-livestock, Coral Reef, invertebrate, reef-tank, saltwater-aquarium, shrimp

Next Page »