Raising Alkalinity

KeitoBombito

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So I have a 5 week old 110gal tank, it has already cycled at around 3.5 weeks and now has a pair of clowns, 1 Zoa frag, and a few snails, all doing amazing. My ammonia is zero-.1 consistently and nitrates around 8-10 consistently ( Red Sea Test ). While wanting to start adding more corals I had tested my alk with my Red Sea test and came back 5, obviously pretty low, so to double check I had my lfs test and my alk came back 5.4 ( so around that 5 mark), calcium 480 (high?), and phosphates 0. My question is would small water changes of 10-15% over the next few weeks to raise alk up to around 8 be my best option? I've heard kalk can be good but it also raises calcium to my knowledge which mine seems on the higher end already, or dosing but the tank is new so I was trying to not get into that yet. Looking for confirmation and feedback, thank you.
 

EnterName

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Assuming the calcium test results are accurate water changes would at least reduce the imbalance between calcium and alkalinity. Usually alkalinity and calcium are consumed in a balanced ratio (but of course there are exceptions). To increase alkalinity without increasing calcium, you can use sodium (bi)carbonate. The balling method (Component B) uses this approach to increase alkalinity.

Note: If your freshly mixed salt water has 8°dH you will never fully reach 8°dH through water changes.
Let's say your current alkalinity is 5.4°dH and you change 15% with 8°dH water. This means the new alkalinity would be 5.4°dH ⋅ 85% + 8°dH ⋅ 15% = 5.79°dH effectively increasing alkalinity by only 0.39°dH. If you do another 15% water change: 5.79°dH ⋅ 85% + 8°dH ⋅ 15% ≈ 6.12°dH. This means alkalinity only increased by 0.33°dH this time. The effectiveness of water changes will decrease the closer you get to the desired alkalinity. Larger water changes are obviously more effective.

In the beginning you can run a tank solely on water changes for quite a while, but sooner or later you will need to add substances that increase alkalinity in a targeted way.
 
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KeitoBombito

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Assuming the calcium test results are accurate water changes would at least reduce the imbalance between calcium and alkalinity. Usually alkalinity and calcium are consumed in a balanced ratio (but of course there are exceptions). To increase alkalinity without increasing calcium, you can use sodium (bi)carbonate. The balling method (Component B) uses this approach to increase alkalinity.

Note: If your freshly mixed salt water has 8°dH you will never fully reach 8°dH through water changes.
Let's say your current alkalinity is 5.4°dH and you change 15% with 8°dH water. This means the new alkalinity would be 5.4°dH ⋅ 85% + 8°dH ⋅ 15% = 5.79°dH effectively increasing alkalinity by only 0.39°dH. If you do another 15% water change: 5.79°dH ⋅ 85% + 8°dH ⋅ 15% ≈ 6.12°dH. This means alkalinity only increased by 0.33°dH this time. The effectiveness of water changes will decrease the closer you get to the desired alkalinity. Larger water changes are obviously more effective.

In the beginning you can run a tank solely on water changes for quite a while, but sooner or later you will need to add substances that increase alkalinity in a targeted way.
That makes much more sense, so using something like baking soda, or would you recommend using a supplement like Red Sea Foundation B or BRS Sodium Bicarbonate Alk Solution?
 

EnterName

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Assuming the calcium test results are accurate water changes would at least reduce the imbalance between calcium and alkalinity. Usually alkalinity and calcium are consumed in a balanced ratio (but of course there are exceptions). To increase alkalinity without increasing calcium, you can use sodium (bi)carbonate. The balling method (Component B) uses this approach to increase alkalinity.

Note: If your freshly mixed salt water has 8°dH you will never fully reach 8°dH through water changes.
Let's say your current alkalinity is 5.4°dH and you change 15% with 8°dH water. This means the new alkalinity would be 5.4°dH ⋅ 85% + 8°dH ⋅ 15% = 5.79°dH effectively increasing alkalinity by only 0.39°dH. If you do another 15% water change: 5.79°dH ⋅ 85% + 8°dH ⋅ 15% ≈ 6.12°dH. This means alkalinity only increased by 0.33°dH this time. The effectiveness of water changes will decrease the closer you get to the desired alkalinity. Larger water changes are obviously more effective.

In the beginning you can run a tank solely on water changes for quite a while, but sooner or later you will need to add substances that increase alkalinity in a targeted way.
That makes much more sense, so using something like baking soda, or would you recommend using a supplement like Red Sea Foundation B or BRS Sodium Bicarbonate Alk Solution?
I personally used pharmaceutical grade sodium bicarbonate, but food grade should be fine as well.

You can also use Tropic Marin Original Balling Component B or BRS Sodium bicarbonate. I wasn't able to find the exact composition of RedSea Foundation B, but the SDS looks like it's also baking soda.
 

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