AQUATIC creatures

Shark life spans vary according to the species. Some live 20 to 30 years in the wild. The spiny dogfish has a lifespan of more than 100 years, while the blue shark in the wild has an average lifespan of 15-16 years and only eight years in captivity.

The Shortfin Mako is the fastest species of shark. It's speed has been recorded at 50 kmph with bursts of up to 74 kmph. On the other hand, the Greenland Shark is the slowest shark with a speed of 2.74 kmph.

Bony fish have gas-filled swim bladders that keep them afloat. Sharks don't have swim bladders. They stay afloat, in part, because their pectoral or side fins work like the wings of a plane, only underwater! Because they don't have swim bladders, sharks must constantly swim.

Sharks are apex predators that have no natural enemies; however, humans are predators of sharks, with an estimated 30 to 100 million sharks killed every year by fisherman.

A hard-shell lobster can live up to 36 hours out of water if kept in cool and moist conditions. Since lobster is a gill breather, wet newspaper and/or seaweed helps keep them moist.

The lack of essential vitamins and minerals in the diets of freshwater and saltwater fishes and invertebrates can lead to health problems, a common one in fish being head and lateral line erosion diseases. An easy way to ensure your aquarium inhabitants get what they require in their diets is to use concentrated liquid vitamins that are high in Omega-3 fatty acids and marine lipids, spirulina and kelp, and other natural nutrients.

Lowering pH: One method to lower pH is to mix distilled or RO water with your tap water to reduce both the hardness and pH. This is effective for smaller pH changes, and you must keep in mind that every time you perform a water change or top off the tank you'll have to mix water. In other words, if you need to greatly lower the pH of your water, think twice – it is going to be an uphill battle.

Raising pH: It's not often that the pH must be increased, as most water sources are already slightly to moderately alkaline. In the event your water is acidic, you want to keep fish that originate from alkaline water. Filtering the water over crushed coral is the method of choice for raising the pH. The use of limestone rocks in decorating the tank will also raise the pH, but keep in mind that you will not be able to adjust it readily. The addition of bicarbonate of soda (baking soda) will also raise the pH and has the added benefit of buffering the water. Keep in mind that this will be an ongoing thing, so you can't add it once and forget about it.