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Coral Vue Hydros

Kh keeps dropping but Ca seems stable?


teenyreef

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I've been dosing two part for a while, but I haven't been able to stabilize my Kh yet - it keeps dropping while my Ca is pretty much unchanged. I've been dosing equal quantities of Seachem Reef Fusion 1 and 2, along with Aquavitro Ions for Mg.

 

Salinity is stable at 1.025. My magneisum stays stable at 1300, and my Ca is right around 430. It may go up or down by 5 or 10 ppm but that's about it and the dosing seems to keep it in check. However, my Ka seems to drop by over .5 kKh per day. I can keep it around 9 dKh if I dose extra quantities of Reef Fusion 2 or by making a water change, but otherwise it keeps dropping.

 

I went out of town this week, so I didn't dose at all. I checked levels right before I left and right when I got back, which was about a four day duration.

 

Mg: 1300 when I left, 1275 when I got back.

Ca: 1420 when I left, 1430 when I got back (huh?).

Ka: 9.3 when I left, 6.4 when I got back.

 

I've seen drops comparable to this in other weeks. The change in Ca might just be due to measurement errors, but why didn't it drop significantly to match the big loss in Ka?

 

I do understand that the same amount of Part 1 makes a smaller change in the Ca measurement than the same amount of Part 2 for Ka.

 

Should I just change to quantitiy of both Part 1 and Part 2 by the same amount until I get the right dose to maintain alkalinity and let calcium find it's own level? Or is something out whack in my tank? Is that much of a drop in alkalinity normal?

 

I think that a .5 dKh drop in alkalinity should correspond to about a 5 ppm drop in calcium if everything is balanced. Is that about right?

 

I use Salifert test kits and Reef Crystals salt. The tank is 4g with some SPS. With such a small tank I'd prefer not to dose but when the alkalinity drops so fast and so low I'm afraid I'd be changing water every two days just to maintain the levels.

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Alkalinity will always drop at a much more rapid pace than calc because it is in a smaller concentration. I can lose up to 1 dkh in a day but my calc stays above 400 with just my weekly water change. I personally find sodium carbonate a very easy way to dose because you can easily calculate how much to add to your water volume to raise the alkalinity however many points you want. Then if you need to ever raise calc it is very easy to add a simple dose of liquid calcium.

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I've been dosing two part for a while, but I haven't been able to stabilize my Kh yet - it keeps dropping while my Ca is pretty much unchanged. I've been dosing equal quantities of Seachem Reef Fusion 1 and 2, along with Aquavitro Ions for Mg.

 

Salinity is stable at 1.025. My magneisum stays stable at 1300, and my Ca is right around 430. It may go up or down by 5 or 10 ppm but that's about it and the dosing seems to keep it in check. However, my Ka seems to drop by over .5 kKh per day. I can keep it around 9 dKh if I dose extra quantities of Reef Fusion 2 or by making a water change, but otherwise it keeps dropping.

 

I went out of town this week, so I didn't dose at all. I checked levels right before I left and right when I got back, which was about a four day duration.

 

Mg: 1300 when I left, 1275 when I got back.

Ca: 1420 when I left, 1430 when I got back (huh?).

Ka: 9.3 when I left, 6.4 when I got back.

 

I've seen drops comparable to this in other weeks. The change in Ca might just be due to measurement errors, but why didn't it drop significantly to match the big loss in Ka?

 

Just wondering, are you testing Alk/Ca/Mg exactly at the same time? (Like you test your Alk/Ca/Mg at 11pm and then the next day, you test them again exactly at 11pm or are you testing it at random times each day?)

 

And when I had SPS, my Alk drops faster than my Ca so I supplemented by adding slightly more Alkalinity and lesser Ca

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Just wondering, are you testing Alk/Ca/Mg exactly at the same time? (Like you test your Alk/Ca/Mg at 11pm and then the next day, you test them again exactly at 11pm or are you testing it at random times each day?)

 

And when I had SPS, my Alk drops faster than my Ca so I supplemented by adding slightly more Alkalinity and lesser Ca

Thanks, and good question. I don't test at exactly the same time but it's almost always late in the evening, between 10PM and 1 AM.

 

I've read conflicting advise on dosing - some people say to always dose the same amount of Alk and Ca because changing one will change the other, and others say to just dose whatever it takes to get each level where you want it.

 

Alkalinity will always drop at a much more rapid pace than calc because it is in a smaller concentration. I can lose up to 1 dkh in a day but my calc stays above 400 with just my weekly water change. I personally find sodium carbonate a very easy way to dose because you can easily calculate how much to add to your water volume to raise the alkalinity however many points you want. Then if you need to ever raise calc it is very easy to add a simple dose of liquid calcium.

Thanks! I'm starting to wonder if if it's really more about just not noticing the much smaller change in Ca. I just got Hanna checkers for Alk and Ca this weekend. They are a lot fussier to use but in theory I should get more precise measurements of Ca.

 

I'm going to be more careful about checking at the same time every night and pay more attention to exactly how much Ca is changing before I decide to change anything else. I do have the BRS two part stuff but I haven't started using it yet, so I have the option of going with just sodium carbonate dosing if I need to.

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Thanks, and good question. I don't test at exactly the same time but it's almost always late in the evening, between 10PM and 1 AM.

 

I've read conflicting advise on dosing - some people say to always dose the same amount of Alk and Ca because changing one will change the other, and others say to just dose whatever it takes to get each level where you want it.

 

It's better to dose to the level you desire; no two tanks are the same and the consumption of Alk and Ca varies for each tank... When I had a bunch of SPS, my Ca dropped faster than my Alk so I dosed more Ca than Alk (9ml of Seachem Reef Fusion P.1 and 2ml of Seachem Reef Fusion P.2)

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  • 1 month later...
  • 4 weeks later...

Sorry for the late followup - yes, I've been able to keep things under control, and I've found that dosing equal amounts of 2 part seems to keep things in line overall. If I reduce the amount of calcium relative to the alk, the calcium eventually drops too much. It just seems to take a lot longer to take effect.

 

I've started using a doser and once I get the settings dialed in I think things will be much more stable.

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