[reefnoob1991]

Hey guys, I went out and got a derasa clam after the addition of my new 150W HQI sunpod, and I just wanted to make sure that that would be enough light. I have a 29 biocube so that gives me 5.2 WPG at about 18 inches of depth

[jimw369]

How big is your Dersa?

[reefnoob1991]

3-4 inches long. 1-2 inches wide

[jimw369]

Cool Beans! Post a Pic

[jimw369]

Read-up! Heres a start!

Giant Clam Basics

Fish and Aquatic Invertebrates » Saltwater Inverts » Clam - Crocea Main Page

[jimw369]

Some more!

Saltwater aquarium tridacna clams page: Maxima Clam, Deresa Clam, Crocea Clam, Gigas Clam, Hipoppus Clam, Squamosa Clam

[jimw369]

MORE!


There are many different species of Tridacna clams, including Tridacna crocea, derasa, gigas, hippopus (This clam is actually in the genus Hippopus, not tridacna), maxima, and squasoma. All of which house zooxanthellae as they grow.

Before you read on, it's important to know that smaller clams depend on regular feedings of phytoplankton. You should aim to get a lot of phytoplankton in the water column instead of target feeding the clam. The clams gills can easily get clogged if they are aggressively target fed. The larger they get, the less they depend on phytoplankton for their nutrients. At around 3," the clams diet usually consists of mostly the zooxanthellae within its tissues, although phytoplankton is still part of the diet.

I'll start with T. derasa:
In nature, T. derasa is found sitting on the sand bottom or coral rubble in shallow waters. As with most clams, metal halides are recommend. However, there have been many successes from hobbyists keeping T. derasa under VHO or PC lighting. For those considering getting a starter clam, this would be one of the species of tridacnids I would recommend. Please be aware that T. derasa is known for getting big in a short amount of time, usually around 20" in aquariums. It's a very quick grower that should be housed in a large sized aquarium.

Tridacna gigas is the largest of all known Tridacna clam species. T. gigas can quickly outgrow smaller sized reef aquariums. T. gigas adapts well to most aquarium lighting. In a tank lit with metal halides, time must be taken to slowly acclimate T. gigas to the light. In nature, T. gigas is found in deeper waters where pH, temperature, and salinity are extremely stable. It is therefore nessisary that you aim to keep these parameters as stable as possible.

H. hippopus is the least demanding of strong light and do well, in most tanks, under VHOs or PCs. If you run metal halides, aclamate it slowly to the intense lighting. The mantel usually doesn't extend farther than the edge of the clam and the coloration is usually brown or green.

Tridacna squamosa, one of the larger species of Tridacna clam and is less demanding of intense light levels. VHO or PC lighting is fine for these clams in most standard aquariums. However, metal halide is recommended for the long run. T. Squamosa is documented of getting up to 12" large in aquariums. They also grow quickly.

Despite the fact that Tridacna crocea is the smallest giant clam species, it is considered to be the most colorful and light demanding species. T. crocea come from similar areas of the reef as T. maxima. However, T. crocea are often found slightly higher up on the reef top where they have evolved to boring into the rock to better protect themselves from strong current and predators. I recommend that not only must they be kept under intense metal halide but also positioned up on the rocks of your reef aquarium. The T. Crocea will usually release an acid based substance used to break down the rock. The Crocea will eventually bury in the rock, where it will be almost impossible to get out.

T. maxima is one of the most common tridacnid species and has the most widespread distribution. T. maxima clams are available in a wide variety of colors and patterns. It's recommend that T. maxima only be kept under metal halide lighting, although a few people on this board have had some success with keeping the T. maxima under PC's or VHO's. T. maxima can often be found in "mutated" colors, such as the Tear Drop maxima. It is usually collected around Vietnam and Solomon islands. Most (if not all) of the Tear drops that came from the Vietnam have died. Many are collected improperly, and are pulled off the rockwork tearing their byssal gland. This usually ends up fatal. In the Solomon islands, many are chipped off the rockwork and do not have damaged byssal glands. Even though they don't have damaged byssal glands doesn't mean they're easy-to-keep.

As with all clams, most should be housed in mature aquariums. In my opinion, around a year is considered "mature" for clams, but, that's only my personal opinion. Many think 7 months, many think 6. Clams should also have a stable calcium and alkalinity level. The clams shell is calcium carbonate based, thus why clams are calcareous invertebrates. An alkalinity of around 8-13dKH and a Calcium of 400-450ppm is recommended. Stable water conditions including pH, temperature and salinity should also be maintained at all times to prevent any stress on the clam.

As with any other creature that you buy, remember to do as much research as possible before buying any clam.

Good luck,
Graham

[reefnoob1991]

You can see the clam in my post about my tank..LOTS of new pics

[Krazy]

Brandon,

The sunpod will be a great light for your new Derasa clam !!!

Congrats !!!

Now get power feeding that anemone so it'll make a come back

[lynnvangsnes]

Wow Jim. You are a wealth of information! Thank you!

[reefnoob1991]

Will it ever eat anything larger? Perhaps shrimp maybe?

[Krazy]

Originally Posted by reefnoob1991

Will it ever eat anything larger? Perhaps shrimp maybe?

The anemone will enjoy "silversides" cut up into smaller pieces like 1/4inch in size.

Larger pellet food, mysis shrmp...

Its going to take a while for teh come back, but at least get it to color back up

[reefnoob1991]

Whoops I meant the clam