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Clams Medium Size

Clams Medium Size

Water Parameters

This is the first place many aquarists will fail. Clams need a tank that has stable salinity (SG of 1.023-1.025) , alkalinity (9-12 dKH), calcium (380-450 PPM), pH (8.1-8.3), nitrates (2-20), strontium (6-10 PPM, utilized in shell growth), and iodine (0.04-0.08 PPM). If any of these parameters falls out of place, the clam will suffer and likely die. Nitrates are usually a problem for SPS keepers, who tend to keep them close to zero. But, clams require nitrates of at least 2 ppm, or they will starve. Calcium and Alkalinity, and the other elements to a lesser degree, are used very quickly by clams and must be tested regularly to ensure you or your doser is dosing enough back into the system to keep up with the clams demand and usage.


This is the second place where most fail. Clams need intense lights, and typically high quality, powerful LEDs or halides are recommended. But, young clams under 2 inches are easily damaged by light. All sized clams need to be properly acclimated to intense lighting. Starting your Tridacnid low in the tank and lowering the intensity of your lights is a good way to start. You can ramp your lights up and move the clam higher little by little every week until it is fully acclimated. Unless you are feeding older clams multiple times a week, most recommend a PAR rating of 250+ is typically recommended, and scientific experiments have shown they are much more productive at PARs of 700-1200. That being said, some do have success keeping clams in 100-250 PAR areas if they are fed well and often. But, I would highly recommend shooting for 250-500 PAR given how shallow the natural environment is for these animals.


Most clams available are under 4 inches. Under 4 inches, most still require supplemental feeding of zooplankton, phytoplankton and bacterioplankton (e.g. PNS Probio™) about twice a week. Unfortunately, I also see mostly 1-2 inch clams in fish stores. At this size, they require these feedings daily for healthy growth and survival. While getting a baby clam can be much cheaper, and you get to watch it grow, remember you will need to dedicate time every day to feed it. Over 4 inches, you can relax on feeding. Many aquarists don’t feed their clams at all as the tanks waste and the clams zooxanthellae are plenty to keep it happy. But, because they do require some nitrates and dissolved wastes in the water column to consume, fish keepers with low bioload tanks should expect to still feed once or twice a week to make up for having fewer fish. This is one area where having a heavily stocked tank is actually extremely beneficial and directly benefits your inhabitants. Clams filter tons and tons of water daily, so they will act as a nutrient sink in even the most overcrowded tank. Obviously, if you are going to have a heavy bioload, do the proper research and stay responsible!


Water movement is crucial. Because they come from shallow reefs, clams are used to strong current and waves. But, most home aquariums rely on plain linear flow. While clams do not prefer this, they can adapt to live with it as long as you set it up correctly. You need to ensure that the water flow doesn’t cause your clams mantle to fold upwards much, and that the clam doesn’t retract its mantle too much. If these things occur, your giant clam will ultimately die. Be sure his mantle is fully extended during the day, and appears to be full, happy, and actively pumping water through its siphons.

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    Our Return Policy

    The Small Print

    If a product arrives damaged, or is incorrect to what was ordered, the customer can contact us for a replacement provided the following conditions:

    Proof of Purchase
    Product has its original packaging 
    Product is unused
    We are contacted within 24 hours of product delivered/picked up
    Shipping costs are non-refundable.

    DOAS, or Dead on Arrival

    Here at Aquaculture Laboratories we provide our customers with the best quality livestock possible by using a ttm method and monitoring our live stock arrivals before selling.

    We monitor our fish throughout the quarantine facility and check them individually before selling to ensure our customers are happy with their purchase.

    For shipping customers, we will replace any fish or coral that are dead on arrival, provided there are photos and we are contacted within 6 hours of the livestock arriving. Photos must be of the coral or fish before bag is opened, and also after bag is opened. Photos must be sent via email to:

    For local customers: should any fish die or become sick, we request to be contacted within 24 hours of purchase and are provided with.

     A water sample to check parameters
    A photo of the dead fish
    Photo and details for your tank including size and tankmates
    Acclimatisation method used
    Shipping costs are non-refundable.

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