That Fish Blog – Aquarium Advice and Information

No matter the profession, everyone has favorite parts of their jobs. One of my favorite “duties” is identifying the livestock we get into our store. Although we used to only offer them as “assorted” individuals, we recently started identifying the Mantis Shrimp we get in whenever possible and they’ve become my new favorite subjects!

Mantis shrimp offer some of the most varied coloration of all the marine animals that enter the hobby. The same species can have a seemingly unlimited array of color schemes depending on where they were collected, gender, surrounding habitat, and a number of other factors. Knowing what to look at as the characteristic and consistent traits is key. Sometimes, especially when they are small, it can be difficult to inspect these aspects without getting closer to the shrimp than you may like or without examining a molt or dead shrimp. Many of the available references use rather technical anatomy terms that may not be easy to understand. Here are some terms that are helpful to know and parts of the shrimp that are helpful to look at when trying to identify a mantis shrimp: Read More »

“Why is that snail just sitting there? Is it dead? Why do they keep dying?”

Common questions with a lot of possible answers – Water quality, mineral or vitamin difficiency, starvation, predation – but often the solution can be quite simple…it fell down and couldn’t get up. Snails crawl around all the time, but falling off of a surface and ending up with their shell on the sand can be a death sentence.

Most snails aren’t adapted to environments where there they may get flipped upside-down (like falling off the straight sides of an aquarium). They are from environments where they are either not climbing at all (like sand flats) or where if they do fall, they either roll until they are right-side-up again or fall where they can reach another surface and right themselves. Being upside-down for short periods of time won’t kill the snails, but it does leave them vulnerable to predation from tankmates, and they can’t feed or do any other normal snail things. Some snails can flip themselves over like acrobats, but others may need a hand if they get stuck. Read More »

Outbreaks of nuisance snails are one of the most common problems encountered in planted aquariums. Though much maligned, snails are perfectly normal in tanks with live plants and can even help with algae control. The problems occur when the snails reproduce and become out of control. Throughout our blog posts, we’ve gone over a number of methods of controlling snails through predators and removal methods, but as with any problems, the problem can be avoided with preventative measures.

A common way of cutting down snail populations is to dip new plants, killing snails and snail eggs before they enter your aquarium. We have here a few different “recipes” for these dips. Keep in mind that while these have been used successfully by many aquarists, sensitive plants may still be damaged. You can try your chosen method on one plant before using it on all of your new plants. These are also all solutions that are to be utilized in a separate bucket, tub or sink – NOT in the aquarium! Read More »

Whether you have a freshwater or saltwater aquarium, rising temperatures in the summer time can be a cause of concern. Aquariums shouldn’t be allowed to get hotter than 83°F, or dissolved oxygen levels in the water will start to diminish. This triggers a competition between fish and invertebrates for oxygen  leading to a very stressful situation, and possibly even death, for your aquarium inhabitants. Detailed below are some tips to help keep your aquarium cool when temperatures rise. Read More »

Iodine is one of the most misunderstood, and misused, elements in the marine aquarium.  Iodine is both essential, and toxic, so understanding your aquariums needs, and proper use, is critical when using Iodine supplements.

What is Iodine?

That is a complex question. In nature, the element Iodine can take many forms, and is one of a group of elements called essential elements. Many are unstable, or play only minor roles in what is relevant to maintaining your aquarium.  The forms of Iodine that are most relevant and form the vast majority of Iodine present in the ocean are Iodide (I), and Iodate (IO₃)

Iodide is an inorganic form of Iodine. Concentrations of this form increase with depth in the ocean, and it is considered the most biologically available form of Iodine.  It is also the safest form of Iodine to use in the aquarium, and most of the Iodine supplements use this form of coral dip to kill invertebrate parasites, bacteria, and other pathogens.

What is Iodine used for in the aquarium?

Iodine is a critical element for cellular function and the transfer of nutrients within cells.  Larger organisms require Iodine for proper thyroid function, production of hormones, and regulating metabolism.  Iodine is utilized by corals for the synthesis of pigments, which allow them to adapt to varying light conditions and provide their tissue with protection from UV radiation.  Invertebrates with exoskeletons (primarily shrimp and crabs in the aquarium) incorporate iodine in to exoskeletons and require iodine for molting and forming new exoskeletons as they grow.

Testing for Iodine

As I mentioned above, Iodine is in many forms, and testing for iodine is a complex issue.  Some test kits measure “total Iodine”. Some test kits don’t tell you what exactly you are testing for at all. Quality test kits, like Salifert, will test for both Iodide and Iodate, allowing you to fully understand what your iodine landscape looks like.  Natural seawater has a total Iodine concentration of .025ppm-0.08ppm, depending on depth and location. It is important to monitor the Iodine levels in your reef, as low levels may inhibit the important biological processes that have been discussed.  Iodine is also a toxic substance, so levels above natural seawater concentrations can be toxic or fatal for invertebrates, and very high levels can kill fish and other vertebrates also.  The standard level to shoot for in the marine aquarium is generally recognized as about 0.06ppm.

Dosing Iodine

Whether you need to actually dose Iodine or not is a topic of debate amongst reef experts. The answer lies mostly in the type of system that you are running.  Iodine is present in salt mix, many additives, and most importantly many foods that you put into your tank. One of the myths that has grown in the hobby is that you HAVE to dose iodine if you’re keeping soft corals and molting invertebrates. While it is absolutely true that these animals demand Iodine, it is also true that Iodine is highly toxic if overdosed, and blindly supplementing with iodine additives can be quite dangerous. Just because you keep these animals, does not automatically require that you dose iodine.

Iodine levels are lowered or depleted by protein skimmers, chemical filtration, and biological processes.  If you are running a heavily stocked, heavily fed fish only (FO) or fish only with live rock (FOWLR) aquarium, you may find that you are maintaining natural seawater levels of iodine simply through water changes and feeding alone.  If you are running a low nutrient, coral dominated, lightly fed aquarium, you will most likely find that supplementation is required to maintain optimum Iodine levels.

There are a number of quality Iodine products available from manufacturers who specialize in marine supplements, like Brightwell Aquatics, Kent Marine, SeaChem, Red Sea and others.

Hopefully you found this helpful, keep an eye open for upcoming blogs about the roles of other supplements for marine/reef aquariums.

Thanks,

Dave