That Fish Blog – Aquarium Advice and Information

Shrimp of various species play an important role in the natural diets of many freshwater fishes, and the nutrients they supply differ from those found in insects and other more commonly-used aquarium foods.  Many native and exotic fishes under my care at home and in zoos prefer shrimp to all else, and do well when they are added to the diet.  And while ocean krill (not a true shrimp) is readily available, I wonder about the long range effects of feeding a marine animal to freshwater fishes.

Unfortunately, freshwater shrimps are difficult for the average aquarist to procure. I was, therefore, pleased when Zoo Med began offering canned freshwater shrimp.  Although marketed as a reptile food, I have fed canned shrimp and find them to be some of the best foods for freshwater aquarium fish, showing great results.  But I’ve been remiss in spreading the word among my hobbyist friends…if you decide to give them a try, please post your thoughts below, thanks.

An Important Consideration                                                                         

Small, whole animals are used in Zoo Med’s canned freshwater shrimp product.  This is preferable to offering our fishes small pieces of food market marine shrimp, which are usually missing nutritionally valuable internal organs (note: food grade shrimp are fine to use on occasion). Read More »

Gorgonians, also known as Sea Fans or Sea Whips, are beautiful and fascinating creatures found throughout the world’s oceans. These creatures are rather iconic, their branched or net-like structures adding a different dimension to a reef, swaying gently with the current.  Gorgonians are flexible, stationary cnidarians though they are very similar to soft corals. Individual tiny polyps form colonies in a variety of sizes and shapes. Some are stiff and erect, resembling the veins of a leaf, some resemble ribbons with polyps aligned on the edges, others look like plumes or are branched like trees. There are also single strand colonies and those that encrust on rock in thin sheets. They are often brightly coloured, purple, red, orange or yellow, and polyps may be white, brown, yellow or some other pale shade.

About Gorgonians

More than 500 described species of Gorgonian are found tropical and subtropical oceans around the world. More species are found in the tropical Atlantic that in other regions. They usually grow in shallow waters, though there are some species that grow in depths of more than 1000 ft. Shallow water species tend to be more flexible and broad to withstand currents while deeper water types grow tall, thin, and more rigid. They may grow anchored to solid surfaces like rock or coral, or they may “root” in loose gravel or sediment.  Gorgonian colonies are supported by an internal, ridid central skeleton covered with softer tissue that connects each polyp to the next to form the colony. The structure a gorgonian colony creates varies between species from a simple whip-like form to complex net-like fans that can be several feet tall and wide.

Gorgonians provide a secure home to many other maring species including brittle stars, bryozoans and hydrozoans. Pygmy seahorses (Hippocampus bargibanti) cling to several specific species and have adapted to blend perfectly with the colonies with color and texture specic camouflage.  You may also find tiny species of crabs, shrimp, gobies, blennies, and other creatures have also adapted to thrive amongst the polyps and branches of Sea Fans.

Choosing a Gorgonian

It’s important to recognize a healthy gorgonian when you’re ready to put one in your tank. Carefully examine your choices, looking for any signs of damage to the skin. Have the person helping you look gently turn each specimen in the water, so you can get a full look, and take notice of any damage, missing tissue, or flaking or peeling of tissue when the specimen is moving. Smell the water in the holding tank. If there is a noticeable odor, avoid the tank, as it may be sign that one or more of the gorgonians is rotting. Look for one with a thick, sturdy, uncut stem or base, and at least a few extended polyps.

Gorgonian Care

Care of gorgonians will vary greatly according to the species you acquire, and you should take care to research the variety before purchase to ensure that you can provide what it needs to thrive.  That being said, most of the common species available in the trade have relatively simple needs.

When you place your new gorgonian in the tank, give it plenty of space where it can sway with the current, completely submerged and without touching other corals or surfaces. Be sure to orient your Sea Fan in good, strong, direct current to ensure they are exposed to plenty of food when it is added to the tank. The water flow will also provide the tissue with plenty of oxygen and keep the surface free of waste and debris. The specimen should be mounted upright and with plenty of light exposure.

Gorgonians are filter feeders. Each tiny polyp has eight tentacles used to catch phytoplankton and other tiny particles carried to them in the current. Many prefer to feed at night, so generally this is when you’ll see the polyps emerge. There are many commercial invertebrate food options available to offer gorgonians. You may also offer them tiny frozen foods like rotifers, cyclopeeze and baby brine shrimp. Administer a small amount of food to entice the polyps to open, then follow a short while later with a larger dose when the most of the polyps are extended.

Many Gorgonians are also photosynthetic, containing symbiotic algae in their polyps that provide a secondary energy source for the colony. Fro these species it is vital that strong light is provided. Photosynthetis species typically have brown or green polyps as opposed to those lacking pigmentation.  These species may grow rapidly when kept in ideal conditions, and periodic pruning may be required. See this article for detailed info on pruning and propogation.

Be aware before you purchase a gorgonian that many fish and inverts may see them as a new meal. Keep a watchful eye for crabs, snails, slugs and other predators that can quickly damage your fan. Gorgonians also play host to lots of other organisms, so don’t panic right away if you find tiny serpent stars, anemones or other creatures from your tank amongst the branches.

Gorgonian image referenced from wikipedia and originally posted by Nobgood
goby on Gorgonian image referenced from wikipedia and originally posted by Jenny (jennyhuang) from taipei

The choices for lighting your aquarium have never been so vast. Whether you are setting up a new aquarium, replacing an old light fixture, or adding to your existing light, there are many decisions to be made.  New technology, and improvements on older lighting methods, provide today’s aquarium hobbyist with a dizzying array of lighting choices for any aquarium. So, how do you choose? What is the best light for your aquarium?

Here are a few questions to ask yourself, to help you with the decision:

Is the light that you are looking for only going to be used on your current aquarium habitat, or are you planning on a more advanced aquarium in the future that may require a higher output light source? You may want to consider a stronger light than you need for your current livestock, as basic lighting may limit what you can keep in the tank down the line.   Read More »

Hello, Frank Indiviglio here. In 2001, I wrote a book about the Natural History and Care of Seahorses. As I intended, many readers were discouraged, due to the demands involved in their care and the fragile state of wild populations. Today, I am happy to report that captive-born individuals of several species are regularly available, and that the task of feeding them (a major stumbling block) has been greatly simplified.  Still, they are not ideal for every aquarist. Following are some important points to consider before you decide to keep these intriguing but challenging fishes. 

Seahorses Need a Wide Variety of Small, Live Foods

The world’s 130+ seahorse species (Family Syngnathidae) are strict live food specialists. Brine shrimp, the most easily-obtained seahorse food, is suitable as a steady diet for only one, the Dwarf Seahorse, Hippocampus zosterae (please see this article). Most others avidly consume brine shrimp, but will not survive long without amphipods (scuds, side-swimmers), sand hoppers, tiny shrimp, Mysids and similar marine creatures. Read More »

There are hundreds of ways that you can make your aquarium “your own”, from the decor or theme you choose to the plants and fish you keep, and even how you choose to accent your habitat with lighting. You may spend a lot of time anguishing on these aspects, hoping to match the vision you build in your head. One aspect that you may not guve the consideration it deserves is the substrate you choose, but the right gravel can make or break the look of your aquarium. This stuff is more than just rocks and sand, it may be the one thing that completes your perfect aesthetic. Let’s look at some of the popular substrate options on the market and explore why one may suit your aquarium better than others.

Freshwater Substrates

If you have a freshwater aquarium, you have a huge selection of substrate colors and types to choose from. First you have to decide if you’re going for a natural look or for something more thematic or colorful. You can purchase colored pebbles or glass accent stones in every color of the rainbow, but some colors are so vibrant they can take the attention away from the stars of the display, your fish.  Colored stones have their place, and can make for a realy fun set-up, but be sure you know what you’re getting into before you purchase a bulk of neon pink or blue substrate. Often these substrates are best as accent colors mixed with natural selections, or for use in smaller tanks.

The natural look tends to be more desirable amongst most hobbyists, shades of grey, tan and brown. These pebbles mimic the textures of creak beds, river shallows, and other natural habitats where these fish come from, making them feel like their back at home. While not all that eye-catching in a bag, these substrates complement the natural colors of live fish and plants, really allowing them to shine. These selections aren’t monotonous either. There are lots to choose from, different sizes, multi-tone, tumbled or rough, that can be mixed or matched to create a custom blend for your tank.  Keep in mind that the size of the gravel you choose may have some impact on fish and plants. Bottom dwelling or bottom feeding fish, and those who breed and nest in the substrate will generally prefer sand or very small pebbles that are easier to move and shuffle, and softer on fins, skin and scales. Likewise, plants may not root well in pebbles that are too large or rough. You may choose to create varying areas in the tank between larger pebbles and finer substrate like inert sand to accommodate several types of fish and plants.  Inert types of freshwater sands are available, but be sure to choose the right kind, otherwise your water chemistry could be effected.

Specialty Substrates

There are also special substrates you can use in your freshwater tanks that not only look natural but also provide benefits to your livestock. These include packaged live sand, flourite/laterite plant substrates, soils and cichlid substrates. Live sand is harvested from a natural wet environment and is packaged with live bacteria intact. These bacteria jump start the cycling process and help to establish marine tanks fast. Plant substrates are naturally colored and sized just right for root establishment. These materials also contribute nutrients to enhance plant growth and vigor. Several substrates on the market are designed to cater specifically to the chemistry and habitat need of Rift Lake Cichlids. These help to maintain pH and hardness, and mimic the rocky appearance of their natural habitats. Some hobbyists also go to the next level for Asian and Amazonian species by creating a soft soil/sand bed using peat, laterite or coco fiber. The natural feel and tannin production helps to make these light-shy fish more comfortable and can make their colors super vibrant.

Marine Substrates

Marine substrates include shell, crushed coral, aragonite sand and similar materials principally composed of calcium carbonate. These substrates will help to increase and maintain pH and hardness. These materials are suitable for all marine set-ups and for Rift Lake cichlids that enjoy similar water chemistry minus the salt. These substrates present little variation from afar, with mostly cream or white coloration with flecks of pink, orange and other naturally occurring shell coloration. There are a few selections that occur naturally in gold or black hues which may be mixed with lighter varieties or used as primary substrate. Incorporating these darker colors may help to keep the colors of your fish more vibrant, as the bright bottom may cause the colors of the fish to appear washed out.

Going Without

In some instances you may even choose to go bare in the aquarium. Bare bottom is usually reserved for med tanks or quarantine systems, but many aquarists opt for no gravel to make maintenance and feeding easier. While this type of set-up has advantages, there are several things to consider before going bare. Some fish may stress easily or not be able to behave naturally if there is no substrate to cover the bottom glass. This method is obviously not a good choice if you want to house gobies or other bottom dwelling or burrowing species. Rooted live plants will not have a place to anchor without a deep gravel bed, so you’ll also be limited to either artificial plants that suck to the bottom or bunch plants that do not need to be anchored in gravel. Substrate also provides a large bed for nitrifying bacteria…be sure to have ample biological filtration, porous rock, or other media to offer the bacteria a place to thrive.

What it all boils down to is taste. The gravel you choose will complete your aquarium’s look and can play a big role in how your fish behave in the tank. Consider the needs of your fish before you make the final decision on how to “carpet” your tank.