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What a lot of aquatic saltwater fish keeper doesn’t know but water quality is one of the most important keys in the failure or success of aquatic saltwater fish. Almost everything you do when it comes to keeping an aquatic saltwater fish enclosure influences the quality of the water or lack thereof. Filtration, aeration, water movement, water source, total surface area, stocking, or even heating all affect the quality of the water. In this article, you’ll learn the importance of water quality when keeping an aquatic saltwater fish.

RO/ DI Water

Let’s start off with some of the most important things you need to know. Whenever possible it’s best to start off with RO/ DI water. Natural seawater would be the best source of water for your aquatic saltwater fish but unfortunately few of us reside near a source that give out safe and filtered seawater.

For the most part, seawater that’s taken out of the sea is usually full of microorganisms that’ll most likely have a disappointing effect on your enclosure. Most of the organisms that naturally live in the seawater will die shortly if you replaced the water in the tank but it means that you’ll need to do more and not less water changes.

RO Systems

In addition to that, aquatic saltwater fishes in your enclosure may come from other parts of the world that are never exposed to such organism’s specific to the area where you’re getting your water. This could easily kill your aquatic saltwater fish as well as other invertebrates which is why for the most part RO/DI water is the best option.

There are great RO systems available on the market today that’ll provide a reasonable amount of water a day without costing you a lot. Much of this water usually goes towards mixing for saltwater and the rest will be used for freshwater top off. Your choice of a synthetic salt mix is also essential because a high quality salt mix from a reputable company will give you consistent batches of water if it was aged properly and mixed well. A highly quality salt mix will provide saltwater with minor elements and acceptable levels of trace, and it can also help you manage the quality of your enclosure’s water.

Water Considerations

Some of the things you need to consider include:

  • High quality water is important but also consistency. So you want the manufacturer to provide a guaranteed analysis rather than mix results.
  • You need to consider some specific guidelines like what kind of gravity you want to have.
  • What is the pH and calcium levels you’re targeting?
  • You need to determine if you’re dealing with the right manufacturer. Does the manufacturer provide a website or contact information where you can get more information on the product?

Saltwater Mix

You need to start off with the best quality of water that’s free of chloramines or chlorine that has minimal to no dissolved solids as well as organic life in it. Add to this water is the right choice of synthetic salt. Do all these things and you’re well on your way to building a great reef enclosure for your aquatic saltwater fishes.

It’s also best that you age your saltwater mix. There are other people that claim that the aging process should be given a couple of days while others usually wait at least a few weeks before using the mixed saltwater. However, lots of people may not have the storage capacity or time to age the water for a couple of days so just keep this in mind.

Salinity for Aquatic Saltwater Fish

You’re not simply looking at the number of dissolved salts within the water whenever you’re looking at the salinity level of water. This is usually measured in parts per thousand.

Specific Gravity is the measurement that compares the density of a liquid to the density of water. Any liquid with a specific gravity greater than 1 is denser than water. Saltwater has a SG of approx. 1.025. Specific gravity is much easier to measure than salinity therefore it is the measurement of choice for keepers of aquatic saltwater fish.

There are a number of tools available for the hobbyist to use to measure SG. Plastic hydrometers that may simply be dipped into the water and read and or glass tubes designed to float in your water. Or you can use a refract – o – meter a device where you place a drop or two of saltwater on the lens, close the lens top and look thru the refract – o – meter eye piece to read the SG. All work well and will normally provide reasonably accurate readings. Although refract – o – meter are more accurate and are becoming more and more affordable.

Do Water Changes Kill Aquatic Saltwater Fish?

The water change can kill all your aquatic saltwater fish. So, how to do water changes? You shouldn’t make a sudden massive change, especially when you didn’t do any of your water changes for months and years before. But, you still need to change your water regularly. First, you should just change less than 5% of the total. After a week, you can perform another change.

You can go on doing this process for several months. But, you should raise the percentage of water changed slightly each time. By this way, you can make a slow change in water chemistry that allows your aquatic saltwater fishes to adapt to without harm. When you are familiar with the water changing routine, you will have to take less time to complete.

Nitrite Poisoning

This problem is also considered as a major killer of aquatic saltwater fish. It can be able to make you lose half your fish to ammonia poisoning even all of your fish. The fact is that ammonia levels are increased, elevated nitrites also follow soon. In order to deal with this problem, you need to test your new tank when setting it up.

Nitrogen Cycle

This problem is also called cycling, biological cycle, nitrification, start-up cycle, the nitrogen cycle, or break-in cycle. Older aquariums also experience periods that the bacterial colonies fluctuate. It’s important to understand the concept of this. Also, you need to know how to handle critical periods during the nitrogen cycle. Just in this way, you can increase your chances of raising healthy aquatic saltwater fishes.



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