Category: Saltwater & Reef

This week’s “Tip of the Week” comes from a question I received from a customer with a Zoanthid-eating Nudibranch problem.

Zoanthid-eating Nudibranchs are what are known as aeolid Nudibranchs, a type of Nudibranch named for the Greek god of the wind, Aeolis. All aeolids eat cnidarians and are frequently named by aquarists based on their preferred prey (e.g. Zoanthid-eating Nudibranchs). Because they feed on ornamental cnidarians, we are generally intent on keeping them out of our aquaria, and that’s what I want to discuss here.

At Blue Zoo, we dip all incoming zoanthids (we dip all corals actually) in a malachite green solution with the primary goal of eliminating as many unwanted pests as possible. The dip works well with all of the soft bodied animals like aeolid Nudibranchs and bristle worms. It will kill some pest starfish as well as some pest snails but it really does a number on their eggs which is really the point of the dip. So the first tip I can offer to you is to ask the retailer if they prophylactically dip their zoanthids. If they don’t, you may want to consider dipping yourself as part of the acclimatization procedure.

I like to recommend a ten minute dip in RO/DI freshwater with Lugol’s Solution. Lugol’s Solution provides a strong source of free iodine and iodide and is frequently used as a dip for stony and soft or leather corals. Keep in mind that Lugol’s Solution is a very concentrated source of iodine—use 40 drops per gallon of water in a separate bucket for your dip. After the dip, quarantine the Zoanthid colony for at least one week. Because the dip will not kill the eggs, it is best to dip the colony every four days or so during quarantine.

Luckily, many individual aeolids are often ineffective at establishing breeding populations that can lead to infestation, so if you do observe a Zoanthid-eating Nudibranch on your Zoanthid colony, simply removing it with a pair of tweezers can be effective. Unfortunately, many Zoanthid-eating Nudibranchs are quite small and can easily proliferate in the aquarium environment making eradication quite difficult.

In these situations, I often recommend a biological approach. In other words, I suggest that aquarists introduce animals that, while consistent with their overall stocking plan, will target and (hopefully) eradicate pests. Using Peppermint Shrimp (Lysmata wurdemanni) to eradicate Aiptasia is a good example of a biological approach to pest control. When it comes to Zoanthid-eating Nudibranchs, There are several fishes that will target them. They include wrasses from the genus Halichoeres (e.g. the Yellow Coris Wrasse, H. chrysus) and Butterfly fishes from the genus Chaetodon (e.g. the Klein’s Butterfly fish, Chaetodon kleinii), but unfortunately, neither can be fully endorsed as reef compatible.

An effective treatment can be to use a product such as Salifert Flatworm Exit. This product is quite safe to both fishes and invertebrates and can be used in a reef tank. To use Flatworm Exit, turn off your UV sterilizer and ozone, and remove activated carbon from the system (keep your protein skimmer turned on). Add one drop of Flatworm Exit for every gallon of system water it in a high flow area of the tank (a cap full is good for 90 gallons). Flatworm Exit will NOT kill Zoanthid-eating Nudibranch eggs, so you should repeat the treatment again in one week to kill all of the newly hatched adults.

 

See also this URL – http://www.coralrx.com/index.php?option=com_content&view=article&id=11&Itemid=23

The Blue Angelfish is a very beautiful fish found in the Gulf of Mexico, Florida, Bermuda and the Bahamas. The juvenile Blue Angelfish is quite different from that of the adult. Juveniles are dark blue with a yellow tail, a yellow area around the pectoral fins, and brilliant blue vertical bars on the body.

Feeding
This small blue angelfish survives mainly on sponges. They enjoy all kinds of live, frozen, and prepared formula foods. Best to feed small amounts several times a day. A good formula that can be made at home consists of mussels, shrimp, squid, and spinach.

Interesting Facts
Adult blue angelfish are generally found in pairs year round, so it is very likely that the male and the female mate for life. Pairs will spawn by slowly rising up in the water column while bringing their bellies close together, and releasing large amounts of eggs and sperm.

A female can release anywhere from 25 to 75 thousand eggs each evening. The eggs are transparent, pelagic, and each contains a single drop of oil to provide buoyancy. The eggs will hatch in 15 to 20 hours. Growth is rapid and 3 to 4 weeks after hatching the fish will reach about 15-20mm and will settle on the bottom.

Recommended Tank Size
The Blue Angelfish requires a large aquarium of about 250 gallons. The tank needs to be equipped with plenty of hiding places so it is okay to decorate it with live rock. Just remember that the Blue Angelfish needs to be able to hide and swim, as it enjoys both activities. The temperature within the tank should be about 72 – 78 degrees Fahrenheit with a pH level of 8.1 – 8.4.

Calcium is used by all salt-water organisms. Some animals use much more than others do; in fact, to some animals, calcium is one of the major components of the diet. Therefore certain types of salt water systems require more attention to the calcium levels. In all salt-water aquariums, calcium must added to replenish the amount consumed by organisms or removed by protein skimming. Calcium monitoring is especially important in reef tanks where a large number of hard or “stony” corals, clams or invertebrates are present. This is due to the fact that these animals use calcium to build their skeletons. In addition, coraline algae also consume calcium. This form of algae is present in all salt water systems, so calcium must be monitored regardless of the type of ecosystem.

Below, we will try to describe the various methods available for monitoring your calcium levels. Of course this is not an exhaustive list, but it is merely a guide for the most common methods for the novice. Talk to a Fintastic employee to determine what is best for you.

Calcium exists in the ocean as the ion Ca2+. This ion is very soluble in water; meaning lots of calcium can be dissolved. For example, in the oceans of the coral reefs, calcium exists at about 400 PPM (mg/Liter of seawater).

When stony corals grow, they consume calcium by the following reaction.

Ca2+ + CO3 -2 → CaCO3

As you can see, the calcium is consumed during this reaction. If calcium is not added to your system, the reaction will slow down, as the calcium becomes depleted. (Notice the other ingredient in the reaction is CO3 -2 . This is the carbonate ion, and we will discuss this compound in the alkalinity lesson).

You can replace the calcium with four methods.

1) Water changes. Obviously, this is the least efficient method for controlling calcium, but it does work. In a thriving reef aquarium, calcium must be monitored daily; therefore; weekly water changes will not be sufficient for this type of tank. For a “soft coral” or “fish only” tank, water changes should be sufficient to maintain calcium.

2) Another method is the addition of Calcium chloride solution. These are the calcium solutions advertised by Kent Marine, SeaChem, etc. Calcium chloride is very soluble in water; therefore, it is very easy to add vast amounts of calcium quickly. However, the disadvantage is that adding calcium chloride also adds chloride. If too much chloride is added, the balance of the total system chloride level will be thrown off which can first appear as an abnormally high salinity reading via a hydrometer when the actual salinity may be low.

3) The third and best manual method is “Kalkwasser” addition. Although very effective, Kalkwasser demands attention to safety, and the mixture can be dangerous to you and your tank. Kalkwasser is simply Ca (OH) 2 dissolved in water (or commonly known as “lime”). Kalkwasser must be prepared before use (within 24 hours) and allowed to settle so that the clear “Lime” water is only added to the aquarium. Kalkwasser must be added very slowly, usually with a drip system or electronic doser. If the solution is added to quickly, then the pH of the system will be sharply increased. A sharp rise in pH will wipe out an entire tank. Speak with a Fintastic employee before engaging in the use of Kalkwasser. Note that mixed Kalkwasser will react with the oxygen in the air we breath and render it useless if allowed to sit out in the open. You must only mix the amount you will use within the 24 hour period to maintain the highest concentration of calcium in the Kalkwasser.

4) Calcium Reactors – This is absolutely the best way to add calcium to your aquarium. The calcium reactor utilizes CO2 to drop the pH of the water circulating within the reactor to 6.5 – 6.2 pH. At this pH, the calcium carbonate material in the reactor will gradually dissolve into the circulating water in the reactor. This will literally raise the carbonate hardness of the water in the reactor to 35-45 DKH. The reactor affluent is then dripped back into the aquarium giving a continual supply of calcium and alkalinity plus trace elements to the system. The single most negative to a calcium reactor is the initial investment into the system. A basic system begins at $850 with the more advanced systems reaching $2,000.