There isn't a short answer to this question so, bare with me.
Depends on your experience. As a newbie, with a new set-up, size is irrelevant,
Ammonia, and
Nitrite tests should be taken daily. The reason is, as a newbie you need to experience the visual signs of the cycle. You need "see" the
Ammonia build up. You need to "see" the
Nitrite build up. You need to "see' them fall to zero. People who take samples of water to their
LFS for testing are missing one of the most important lessons in basic aquariology. Once a cycle happens, it's not necessarily over in a new tank, especially a small tank. In a small volume of water, you have something die behind the rocks, you could easily have an
Ammonia spike that causes havoc in your system. Larger tanks are more forgiving, in many ways. Once you have witnessed the cycle, then testing once a week for a month just to be sure. After that once a month or even less would be fine. After the cycle has completed, you can begin testing for
Nitrate.
Nitrates in the range of 0 - 10
ppm are safe. Above 10
ppm trouble begins. Regular 20% water changes, from the beginning, will help alleviate but not eliminate
Nitrate. A deep sand bed (DSB) and a
refugium will do that nicely.
Calcium, Alkalinity,
pH and Magnesium (THE IMPORTANT FOUR) are very important tests that should be taken on a regular basis. In the beginning of a new system, after the cycle has happened, test for all four. Record your findings. Here's a typical sample of readings you might find with newly mixed artificial sea water and the values of
NSW (natural sea water). Calcium 350
ppm -
NSW 450
ppm, Alkalinity 4 meg/L -
NSW 2.5 meg/L (In an aquarium, it is better for
pH control and improved Calcium stability to maintain a higher Alkalinity),
pH 8.0 -
NSW 8.0, Magnesium 850
ppm -
NSW 1250
ppm. These figures for artificial sea water are typical of salt mixes and will vary depending on brand. Why do they fall short of
NSW? That's a good question. I've never heard a good answer.
After testing for and raising the levels to match or exceed
NSW your aquarium is in tip top condition for adding specimens. Once you begin stocking with corals, fish and other things those prime water parameters will change due to the inhabitants' natural absorption through metabolism. It happens 24/7 and you can expect your water conditions to change. This is why we test "The Important Four" as I call them. Of the four, Magnesium is the most neglected, yet one of the most important. It is impossible to maintain Calcium levels at or above 450
ppm without maintaining high Magnesium levels. They work together. People call all the time and complain about not being able to get their Calcium above 350
ppm. It's always because they are not testing Magnesium levels and haven't learned the important connection between Calcium and Magnesium. Now you, and everyone else that reads this post, knows that importance. Test for and maintain Magnesium levels between 1250 - 1350
ppm. Your system will reward you with great coral growth and healthier fish and other critters.
I dose
Ocean's Blend Two Part Additives and Magnesium daily. I test the "Four" once a month. It's a matter of setting priorities. This is an expensive hobby. It is less expensive to maintain optimum water conditions than to replace dead specimens because of failure to learn the "right way" to do things.
Besides all that, there isn't a non ending supply of reef inhabitants for collection. The demand is extremely high and the supply is dwindling. Plus, we've all heard the alarming news of the sad condition the World reefs are in due to mans destructive ways. As a responsible person, it's only natural to give our best attention to our captive piece of the reef. Reefing
requires us to be constantly learning, desiring to do better, striving to keep our critters in optimum health for their longevity. Keeping excellent water parameters is just the beginning.
Thanks for reading this very important post.
Happy reefing.
Dick
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