What to test for post-cycle:
1. alkalinity---this governs 'comfort' of the water: low alk can lead to very unhappy fish, for starters. It governs the ability of the water to dissolve things like calcium, etc, and keep it available. Keep alkalinity at about 7.9 to 9. It can go higher, but my own preference is 8.3, middle of the range, lot of wiggle room. If it drops below 7.9 on the DKH scale, fix it with an alkalinity buffer of some sort. I use Kent DKH buffer. ALk is related to ph, but don't bother chasing ph in a marine tank: it's different for marine, and alkalinity is your best gauge of water conditions.
2. salinity---range between 1.024 and 1.026 for a reef and inverts; 1.019 and 1.026 for a fish-only.
3. temperature---steady, somewhere close to 79 degrees F.
4. magnesium---a key chemical that will stabilize your alkalinity at 8.3 (given you have enough buffer in the tank) and your calcium at 420, which is a good reading. If your mg is low, you can add buffer and calcium until your pipes go gunky with no lasting improvement. If readings drop persistently, look to your mg level.
5. Note that stony corals, clams, and coralline etc, will use up calcium, so that replacing calcium becomes essential. If you are buffered to at least 8.3 and have mg set at 1350, you can just add lime (calcium) to your topoff water and have very stable readings for months on end---just keep adding more ro/di and more calcium to your topoff reservoir. Calcium in this form is referred to as 'kalk'. This stability means that, with a large enough topoff reservoir and an ATO, you can go on vacation for a month and come back to well-fed and happy corals, granted your fish are on autofeeder and are poo'ing nutrient into the water.
6. calcium reading---420 is good. 410 is too little for stony coral and clams to be happy.
7. are fish happy in reef-chemistry water? Yes. Their skins are happy with the alkalinity (which is controlling the ph) and their bones have enough calcium (though they use it far more slowly than a coral does) and their general chemistry, muscles, etc will be happy with enough magnesium... Those three situations are critical for corals, but fish are quite happy tootling about coral reefs, too. Because that chemistry situation is easy to lock and hold in place with kalked topoff, it means your whole tank chemistry can stay happy for long periods of time without your having to do anything.
8. need for a skimmer....corals are living filters, and soft and lps stony and some inverts do feed off nutrient in the water. But in our closed tanks, stuff can pile up in excess. Excess of protein waste (amino acids) can make the water unpleasant: a skimmer pulling skimmate is a good thing. This blackish soup would otherwise be in your water being nasty. If you have high nitrate and want to get it down, a better skimmer can help, but you can also increase the skimmate production of a weaker skimmer by dosing something to feed the bacteria---I use NoPox.
9. never forget to test nitrate and ammonia. Nitrate is VERY apt to build up in a system using only a filter, or sponge, and in fish-onlies in general. ANY ammonia at all is an emergency, and calls for water changes and removal of ammonia ASAp, as it is a killer, especially of fish---corals actually survive it better than fish do. But always try your best to keep your nitrate as low as possible. A coral reef would like to have nitrate nearly undetectible, faintest pink on the tests; and a fish-only would love to have it under 20 (though this is pretty hard for a fish-only to reach) At least keep chasing that goal, but fish can survive high nitrate, above 50.
1. alkalinity---this governs 'comfort' of the water: low alk can lead to very unhappy fish, for starters. It governs the ability of the water to dissolve things like calcium, etc, and keep it available. Keep alkalinity at about 7.9 to 9. It can go higher, but my own preference is 8.3, middle of the range, lot of wiggle room. If it drops below 7.9 on the DKH scale, fix it with an alkalinity buffer of some sort. I use Kent DKH buffer. ALk is related to ph, but don't bother chasing ph in a marine tank: it's different for marine, and alkalinity is your best gauge of water conditions.
2. salinity---range between 1.024 and 1.026 for a reef and inverts; 1.019 and 1.026 for a fish-only.
3. temperature---steady, somewhere close to 79 degrees F.
4. magnesium---a key chemical that will stabilize your alkalinity at 8.3 (given you have enough buffer in the tank) and your calcium at 420, which is a good reading. If your mg is low, you can add buffer and calcium until your pipes go gunky with no lasting improvement. If readings drop persistently, look to your mg level.
5. Note that stony corals, clams, and coralline etc, will use up calcium, so that replacing calcium becomes essential. If you are buffered to at least 8.3 and have mg set at 1350, you can just add lime (calcium) to your topoff water and have very stable readings for months on end---just keep adding more ro/di and more calcium to your topoff reservoir. Calcium in this form is referred to as 'kalk'. This stability means that, with a large enough topoff reservoir and an ATO, you can go on vacation for a month and come back to well-fed and happy corals, granted your fish are on autofeeder and are poo'ing nutrient into the water.
6. calcium reading---420 is good. 410 is too little for stony coral and clams to be happy.
7. are fish happy in reef-chemistry water? Yes. Their skins are happy with the alkalinity (which is controlling the ph) and their bones have enough calcium (though they use it far more slowly than a coral does) and their general chemistry, muscles, etc will be happy with enough magnesium... Those three situations are critical for corals, but fish are quite happy tootling about coral reefs, too. Because that chemistry situation is easy to lock and hold in place with kalked topoff, it means your whole tank chemistry can stay happy for long periods of time without your having to do anything.
8. need for a skimmer....corals are living filters, and soft and lps stony and some inverts do feed off nutrient in the water. But in our closed tanks, stuff can pile up in excess. Excess of protein waste (amino acids) can make the water unpleasant: a skimmer pulling skimmate is a good thing. This blackish soup would otherwise be in your water being nasty. If you have high nitrate and want to get it down, a better skimmer can help, but you can also increase the skimmate production of a weaker skimmer by dosing something to feed the bacteria---I use NoPox.
9. never forget to test nitrate and ammonia. Nitrate is VERY apt to build up in a system using only a filter, or sponge, and in fish-onlies in general. ANY ammonia at all is an emergency, and calls for water changes and removal of ammonia ASAp, as it is a killer, especially of fish---corals actually survive it better than fish do. But always try your best to keep your nitrate as low as possible. A coral reef would like to have nitrate nearly undetectible, faintest pink on the tests; and a fish-only would love to have it under 20 (though this is pretty hard for a fish-only to reach) At least keep chasing that goal, but fish can survive high nitrate, above 50.
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