Low-Tech Marines By Deborah Ralph

 

In the club, there seemed to be a definitely negative response to the idea of keeping marines in the home. It was always "it's too hard", “you need a trickle-filter, UV-sterilizer, protein skimmer, etc." or "you'll never be able to keep a small aquarium's water stable" and so on. Most of the books and magazines seemed to agree with this negative attitude, so we did not even attempt to keep a marine aquarium. Why should we when, according to most views, we would need to win Lotto and have a degree in marine biology to have any chance of success. Then, a couple of years later, we were told there was light at the end of the tunnel. The Boyds got brave and set up a 2'x2'xl'marine aquarium. After having read a number of TFH articles, they had decided to take the plunge on a small setup, using the semi-natural system as described by Dr Cliff W. Emmens, plus a few other ideas from elsewhere. Their aquarium had been set up for only a short while, with but just a few pieces of living rock. However, it was still fascinating to watch as more tiny bits of life were noticed on the rocks each time we visited. Right then and there, we decided to begin our own marine aquarium along similar lines. The Boyds were questioned continuously (it didn't even need bright lights) and we read any books we could find on marine and invertebrate aquariums. One of the most informative of these was "Marine Fishes and Invertebrates in your own Home" by Dr Emmens, which gave us a few different ideas about setting up, plus a lot of hope that it could be done in our own home.

 

The semi-natural system uses some mechanical filtration but also relies on living rock to supplement the process in the natural way. We knew it would still be a challenge but this way, at least it would be more affordable and more natural looking.

 

For a start, we had to decide which freshwater aquarium to sacrifice and we settled on a 30"x14"x18" for our first marine tank. It was thoroughly cleaned and given a base of washed medium-grade shellgrit (a 50 kg bag from a produce store cost about $12.50), a depth of about 1" in front and 1.5" at the back. The tank was filled with tap-water (90 L) and allowed to stand with aeration for 3 days, to disperse the chlorine. Then the marine salt (Instant Ocean brand) was added, with stirring, and a further 1-2 days were needed for it to dissolve completely. About 12 cups of the salt were needed to give a specific gravity of about 1.022 ' which was fine, as the acceptable range is 1.020-1.025, the lower side being better for fish but the higher better for invertebrates. So a middle-of-the-range value should suit both groups, as long as it was kept fairly stable. Tap-water in Canberra at present is hard, with a pH of about 7.8, which is just about right for marines.

 

We supplemented the airstone and powerhead in our tank with a boxfilter containing shellgrit seeded with marine bacteria from the Boyd's aquarium and placed some clean filter wool on the top. This was the only, mechanical filtration used. For 'kick-starting' the biological activity in; of the aquarium, we followed an article in TFII July, 1986, but instead the chopped clam advocated there, we used chopped scallop, about one tablespoonful, finely divided. For the next few days we drew straws to decide who should go into the fishroom and open up for the mornings: it was rather hard on the nose, though only for a couple of days, since the scallop broke down quite quickly. The water temperature was 25C and after two days, we began testing for ammonia and nitrites. Whilst we knew what to expect, from reading books, we were interested to keep records (for later use maybe) of the ups and downs in our first marine, aquarium. Over the following days, as predicted, the ammonia level was first to rise, then the nitrite. The nitrate level could not be tested until the nitrites were down far enough. After 11 days we were too impatient to wait any longer and purchased a few small bits of living rock, for testing purposes only. They all did well and so did the life on them. On the 14th day the water was again tested and we had marine quality, ready to go: ammonia nil, nitrite nil and nitrate nil. The tank now had a few bits of living rock, with some interesting forms of life on them, enough to keep us fasciated (it didn't take much). Each day we would notice new life, such as little corals, feather dusters, small anemonies, algae, etc.

 

Just as the first marine aquarium was almost ready to receive its initial bits of life, we started another one for quarantining. This was only 28L but it still took two weeks to be ready. Setting up a marine aquarium is like beginning the fish hobby all over again; there are so many new and different things to learn about, that have to be done carefully. It also teaches patience, as it is a slow process, but it's better to avoid the temptation to speed things up, with the risk of wasting a lot of hard work, not to mention the salt (= money) that may go down the drain.

 

We provided an anemone for future Clownfish (always thinking ahead) in our no.1 marine aquarium, after it had been stable for a week (3 weeks after the scallop was added). We were now completely 'hooked' and scrutinized all of our remaining freshwater tanks, to choose the next to be transformed. A 5'one, which already had a Fluval 303 filter, was selected, as we felt we might as well make a proper job of it. This aquarium was set up in the same way as before and, after allowance for rock, etc., the water capacity was 244L. Once again, it took only 14 days to achieve nil readings.

 

We had ordered a box of living rock and it arrived on the right day, when the tank was ready. We were glad to have kept those records, which made things easier. It is best to obtain living rock by the box-full as it is then supplied direct, rather than in and out of shop aquariums. We were sharing the consignment with the Boyds, a quarter for them, so the 8 pieces were placed out, still wrapped, on a plastic sheet. Andrew chose 2 and the rest were ours. This was the fun part and now we would see some interesting forms of life. We made certain to remove any mantis shrimp we could find, before placing the rocks into the aquariums. There was plenty of other life, including small crabs, brittle stars, growths of small corals, sea squirts, etc. One large rock was half covered with hard coral. It was difficult to decide where to place the various rocks, but there had to be ample spacing between them, to allow good water circulation, until they had recovered from their journey.

 

Yes, you've probably guessed it: we had got the bug badly and sacrificed more space for yet another marine aquarium. This, however, was to be only a small aquarium ((1 8"x 14"x 1 2") for the lounge room, so we had Graham Maloney make us a tank that fitted the alotted space to perfection. We cheated this time and after adding the shellgrit, we 'borrowed' some water from the 5'aquarium (only 36 L were needed). The top from an internal power-filter (that was otherwise useless) was used to circulate the water, a 12" airstone was fitted for aeration and the only filtration was a sponge-filter. The sponge had been soaking in the 5'aquarium for over a week (we must have had a premonition we might need it). A couple of days later, two smallish pieces of living rock were moved to this new aquarium and the no. 1 marine aquarium was given a nice and larger piece to compensate.

 

Our marine aquariums were still missing something: colour and movement. Was it time for fish? No, not yet, but certainly corals. These beauties were not cheap but as some of our holiday pay had already gone on setting up the tanks, we decided to use the rest on a box of coral. This would complete the scene and make it ready for the fishes. As we collected our box of coral, an anemone caught our eye and this was also brought home. Unfortunately, the coral had missed its scheduled flight and had been trucked down overnight. so there were a few losses and some extra problems to cope with. The bad corals were easy to tell by smell alone, so only the good ones were placed in the 5-footer. Because of the delay there were probably other dead things on them, and these caused the levels of ammonia and other toxins in the 5'aquarium to rise. All we could do was wait and hope that everything would be alright and as it happened, it took 6 days for the water conditions to ease back, although most of the corals came through. The anemone and living rock seemed unaffected by the adverse water conditions, so we heaved a sigh of relief. We had some spectacular corals (presumably the more adaptable ones) survive but we might have done better by purchasing them separately and building up the number over time, so as not to unbalance the water conditions. Now, with the losses, the cost was about, the same but, as they say, you live and learn. Anyway, 10 days after the coral had been added, all was well again and our spirits were not dampened.

 

We purchased a pair of Maroon Clownfish (Premnas biaculeatus) for no.1 aquarium, for it was only fair that it should have the first fish. This aquarium had now been running for almost 3 months. The living rock and corals were rearranged and terraced (some on top of river rock) to our satisfaction in all but the quarantine aquarium, which had only had a piece of dead coral, with some algal growth. All except this quarantine tank were lit from above by one Triton tube but the 5’ had an Aquaglo light tube as well. We put a pair of Salmon Skunk Clownrish (Amphiprion periderain) and a small Coral Goby (Gobiodoh citrinus) in the lounge aquarium. A Royal Dottyback (Pseudochromis paccagnella) joined the pair of Maroon Clownfish in no.1 setup and at present in the 5' tank are a pair of Fire Clownfish (Amphiprion melanopus), a Royal Dottyback, a Cleaner Wrasse (Labroides dinzidiatus) and a Moorish Idol (Zanclus canescens).

 

After the addition of the living rock and corals, there was the question of what to feed these invertebrates. They contain symbiotic algae and therefore need mainly animal protein as a source of nourishment. Since their way of feeding differs from that of fishes, they need very fine foods and there are propriety brands available, as well as others that may be less obvious. I have used liquid invertebrate foods as well as other things, such as Nutra Fin tablet. This crushes up nice and finely, so I crumble one tablet into the 5' aquarium (and smaller portions for the others), for a change. We were surprised how quickly fish that we had thought would be difficult adapted to aquarium life. At first, they were given special frozen food for marines, green food, marine cocktail and frozen bloodworrns and they ate all of these readily. They were fed once a day, had healthy appetites, and weren't as fussy as we expected.

 

When these fish are hungry and they realise what is dropped in is food, they will try most things and can also become very friendly. So far, they have eaten most of the foods that we give to our freshwater tropicals, such as freeze-dried Tubifex, bloodworms or Pacific plankton, marine flake, brine-shrimp flake and pellets. The Moorish Idol has a fondness for Wardleys cichlid ten floating pellets and Tetra Dorogreen but also eats all of the other foods mentioned. The anemonies are given a piece of fish weekly or fortnightly, according to their size and appetite, but the clownfishes also feed them a little with other foods. When the chopped fish is given, a little is also squashed up for the fish, who take it with relish. Live or frozen daphnia are also given, when available and we give the marine aquariums a little squirt of newly hatched brineshrimp daily, as we do our rounds to feed fry in our freshwater tanks.

 

After one month the aquariums were given weekly doses of trace elements plus marine plant/algae food. Water tests were also carried out weekly for the first few months but as everything was remaining stable, they were then reduced to fortnightly. However, the aquariums are still visually checked daily for any signs of trouble and we try not to overfeed. Periodically (every 2-3 weeks) the tanks need topping up because of evaporation, leading to increased specific gravity readings; this is done with aged tap-water. At the time of writing, the no.1 aquarium (which was set up in early June 1990) has been running for a little over 5 months.

 

Dr Emmens states in his book that in natural-type marine setups water changes are necessary occasionally but that as little as 10% every 2 months may be sufficient. Monitoring the water conditions will indicate when such changes are required. We realise that we are still in the early stages with our marine aquariums but are happy with the progress so far, most but not all of our corals have grown, the living rock appears to be keeping to its reputation and the fish are doing well, although only a few can be kept in a natural system. It is nice to have a few tanks set aside for decoration and viewing only, however one day, a pair of anemone fish may decide to spawn and ruin that idea and wouldn't that be a shame! There have been some losses of coral and fish along the way, and a few mistakes made, but we are glad we gave it a try.

 

There are quite a number of books and magazines dealing with marine aquariums, invertebrates and fishes and I would like to mention a few others that we found useful. These include "The Marine Aquarium" by Dick Mills and the following articles from TFH: "Marine Aquariums made easy"; parts 1,2 and 3 by Raymond Hunziker (July, November and December, 1986) and "The Mysterious World of Anthozoans" (corals, anemonies and their relatives), parts 1 and 2 by Peter Wilkens (July and August, 1990).

 

Points to remember when aquarium.

 

  1) Make sure the water quality is stable and tests are right before adding living rock, corals and other invertebrates or fish.

  2) Do have a quarantine tank, where any new fish should be kept for 2-3 weeks.

  3) Choose only a few fish for the low-tech aquarium, as it will have a low carrying capacity, and make sure the fish are compatible with the corals and other inmates.

  4) Monitor the water quality frequently and top up only with aged water, either fresh or artificial salt mix.

  5) Do not overfeed fish or invertebrates and have patience when trying new foods or feeding new fish. Uneaten food must be removed promptly or it may overload the system.

  6) Clean tank lids frequently as corals, etc. need good light to survive.

  7) Ensure that there is plenty of aeration and water movement.

  8) Do have some reputable dechlorinator available, suitable for salt water.

  9) Keep a stock of marine salt on hand for those water changes.

  10) Research as much as possible the natural habitats of the corals chosen, to determine appropriate lighting needs and water movement levels.

  11) Research the invertebrates contemplated, as some may devour corals or other intended inmates (some cowries eat corals, anemonies eat small fish, some invertebrates can poison tankmates and even humans, and so on)

 

Finally, read all you can about marine aquaristics, enjoy your own collection of interesting creatures and have fun!