Formosa Forest

Posted on February 9, 2011 | 2 comments

Aquarium Profile

The Formosa Forest is a custom build rimless all glass tank, measuring 32” x 32” x 21”. The total system incl. Sump is 100 Gallon in volume. The overflow is centered in the back of the tank.
The stand is a steel frame, with removable panels, for easy access to the sump and equipment. The aquarium has an open top, so there is no canopy. I think this gives the tank a sleeker look, and it prevents heat-issues.

Lighting the Formosa Forest

I think the lighing is the part that I changed the most. I got good results with the setup that I used the last year. I DIY an HQI+T5 pendant, by connecting 2 T5 pendants from Aqua-Connect to an Aqua-Medic Aquaspacelight pendant. I removed the ballast from the Aquaspacelight, allowing me to add another 250 Watt HQI bulb to it. Both the ballast are external now.
I custom made a large aluminium spider reflector inside of it.

I used 2 Aqua-Connect 250 watt HQI bulbs combined with 2 Aqua-Science blue 22000 K T5 and 2 Giesseman aquablue+ T5. The total light is 500 Watt HQI and 96 Watt T5.
I have used other bulbs, but I’m the most content with the Aqua-Connect bulbs. I like the blue hue of them, they really make the colours “pop”. I use the T5 bulbs for some extra blue accent and to create a nice dusk/dawn effect.

I ran my HQI for 10 hours a day and the T5 for 12 hours.

Watercirculation in the Formosa Forest

I think water circulation is the most important thing in a reef tank system. Most importantly it provides oxygen to all living organisms. Besides that it keeps the detrius suspended in the watercolumn, creating a valuable foodsource for sponges, tunicates, featherdusters, and -of course- the corals. It also gives you control in the amount of detritus that will be skimmed off, but later more about that.

The flow was provided by 2 Tunze 6100 pumps, pulsing 30-50% every 15 seconds, creating a random flow throughout the tank. I the back I have placed a Tunze 6025 NanoStream, that I modded. It prevents the accumulation of detrius behind the central rock. The large returnpump also created a good amount of flow.

Filtration and Equipment

The skimmer that I used in this tank was a MTT1 Venturi skimmer (ATI-Twister clone, but with venturi) I chose this skimmer because I like the venturi-type skimmers. These skimmers are pumping a lot of water and air, creating slighty larger bubbles then needlewheel skimmers. The larger water/airflow and the larger bubbles allows the skimmer to push heavier particles in the collection cup. I can skim both wet and dry with this skimmer. Once you have ajusted it, you only have to clean the collection cup every 2 to 3 days.
I adjusted the skimmer this way; I found a balance between nutrients/algae and healthy/fed corals. The skimmer now skims semi-dry; It removes the organics fast enough to prevent phosphate/nitrate elevation, but not too fast to starve the corals.
In the sump I placed a small RDSB. I decided to use one after I had problems with pale couloured corals. Colours were better after the implement, I think the RDSB stores and release some nutrients. Another advantage is that my Nitrates were always unmeasurable.
I had a DIY a Phosphate reactor that is placed in the sump. I always used a small amount of GFO, to make sure the Phosphates remain unmeasurable. When algae growth on the glass increased, I knew it’s time to replace the GFO. Usually I replaced it every 2 weeks. At the same time I replaced the GAC, that was helded in a filterbag in the sump, between 2 baffles. I used around 3 tablespoons of GFO and GAC constantly.
The large return-pump (1530 G/h) helped me to circulate fresh skimmed/filtered/oxygenated water and tankwater fast, creating a healthy environment in the tank. It also prevented detritus from collecting in the sump.
Four computer fans helped me to keep the temperature around 79 Farenheit. It switches on when the HQI were burning.
I didn’t use auto-toppoff or Calcium/Kalk reactors.

Maintenance of Formosa Forest

The daily maintenance consisted of checking the equipment, temperature, and feeding/checking the inhabitants. I checked if all the inhabitants were there, and make sure their behavior was normal. I cleaned the skimmer when the cup is full, every 3-4 days. Cleaning of the glass was done every 2-3 days.
Topp-off was done by hand every day. I dosed 6 ml of Tropic Marin K+ and A- elements every day, together with 4 scoops of Tropic Marin Bio-Calcium. This kept my Alkalinity and Calcium on the right levels. 0,5 mg of sugar was added everyday to reduce the Phosphate and Nitrate levels and to keep the water crystal-clear.
Every 2 weeks I did a 18 Gallon Waterchange with KorallenZucht Reefers-Best Premium salt. The skimmer was taken out and completely cleaned once a month.



I love small, schooling fish, especially from the Apogon Genus. They really “ use” the Staghorn-branches to hide in. This natural behaviour gives appereance that the tank is one ecosystem; fish and coral integrated. I kept 9 Apogon Leptacanthus.
Besides the Apogon there are 3 tangs in the tank. Tangs are great fish, they eat a lot, so their waste provide a great food source for the corals and other invertebrates. They also graze the rocks, that way algae have no chance.

I bought them when they were 1,5-2” large. When they are that small, they can be kept in a tank this size.
I never have experienced any aggression of fighting between the tangs. Sometimes the Convict Tang “impressed” the other two by spreading it’s fins, but that’s it.

I wouldn’t start any reeftank without a Salarias Fasciatus. They are great algea eaters and have a great personality. My Salarias even eats the excrements of the other fishes, reducing the pollution of the water that way.

Apogon Leptacanthus
Acanthurus Coeruleus
Acanthurus Triostegus
Zebrasoma Flavescens
Salarias Fasciatus
Pseudocheilinus hexataenia
Myripristis Jacobus

Corals creating the Formosa Forest

Corals are the reason I keep a reef aquarium. Fish make a nice addition, but the corals are the most important for me.
I especially like staghorn corals. That’s why I created a reeftank with mostly staghorns. Most of the staghorns are bought from fellow hobbyists, that way I didn’t start with small frags, but with staghorns about 4” big. Because staghorns grow and branch fast under the right conditions, my tank was becoming a “Formosa-Forest” relatively fast.
To give the tank a more diverse look, I also keep Zoanthus, Montipora and several different LPS corals.


Acropora Formosa
Acropora Microphthalma
Acropora Hoeksemai
Acropora Yongei
Acropora Nobilis
Acropora Elseyi
Acropora Millepora


Montipora Digitata
Montipora Danae
Montipora Confusa


Favia spec.
Fungia spec.
Pectinia spec.
Pocillopora Damicornis
Seriatopora Hystrix


Zoanthus spec.

Other invertebrates;

I always liked to keep small invertebrates, such as shrimp, urchins etc. because they pop up once in a while and it’s always fun to discover them.
Because they’re mostly detrivores, they keep the tank clean by eating detritus, food particles and algae where the fish can’t reach. Another advantage, the peppermint shimp also eats Aptaisia.

Echinometra spec.
Lysmata Wurdemanni
Trochus niloticus

Feeding the Formosa Forest

I fed a lot, because I think you have to feed not only the fish, but the whole tank indirectly. That’s why I think diverse, high quality food is important for the reeftank to be diverse and healty.
With the heavy flow, large skimmer and GFO I felt safe enough to feed a lot. Heavy skimming does remove valuable trace-elements that corals need to be healthy. That’s why Tropic Marin A+ and K- elements were dosed daily. Tropic marin Biocalcium provides, besides Calcium and Alkalinily, also the 70 elements found in NSW in the right proportions.
The fish were fed 2-3 times daily with small amounts of food. 2 times dry food, and one time frozen food. I vary with the food from day to day, to create some alternation.


O.S.I. Spirulina Flakes
New Life Spectrum Thera A+ granules
Frozen Mysis
Frozen Artemia

AEFW Infection in the Formosa Forest

I had an Acropora Eating Flatworm Infection, and a couple of times after that in the Lagoon. I had to completely break down the tank and remove all corals from it’s base. All corals with egg-packages were trown away or fragged. I dipped all the Acropora corals and all the LiveRock that was in the tank.
In the first dip I used a combination of Levamisole and Tropic Marin Pro Coral Cure (TMPCC) I gave the corals and liverock a 15 minute dip. Many flatworms were coming off the coral and were floating around in the treatment container.
The second dip, 2 weeks later, only contained TMPCC. I did a 10 minute dip, and only a few flatworms came off after blasting the corals with a nano-stream. I didn’t find any small flatworms, only a few larger ones. This made me conclude that there were no eggs that hatched. Unfortunately the AEFW came back after several months.

 After a few encounters with AEFW I found the best way to treat them. Read more about it here.


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  1. Hello from Germany,

    wow you have done amazing jobs with all the tanks! Really. Would you please tell me how you do the filtering while the tanks look like there are only the corals inside.

    Continue doing that great!

    Greetings and best wishes,

  2. Yeah! I agree on you Flo! Those are really great! Keep posting Mr.!

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