Testing KH VS testing Ca and Mg

[Muffin87]

This is the testing routine BRStv suggested for an LPS tank.

 

Why is testing KH more important than testing Ca and Mg?

Why do I want to test KH more often?

Isn't KH consumption directly related to calcium consumption, so that the two are consumed at the same rate?

 

Thanks!

[Clown79]

I test salinity and alk weekly

 

The rest monthly

[SliceGolfer]

Usually KH is consumed at a greater rate than calcium, and calcium at a greater rate than magnesium. There are times where you may see a dip in calcium over KH, but the standard is KH depletes faster than Ca. Personally, I test KH twice a week, on Wednesday and Saturday. I test Ca, Mg, and others once a week, on Saturday. KH is the one element that can have an adverse effect on your tank if it skyrockets. Low KH has an effect as well, however the severity of lower KH is less dramatic than KH rising quickly. There will be times you'll need to dose a little more KH or more Ca to balance things out. Then you can continue with your basic two part dosing routine. Testing KH once a week is a minimum for me, however a mostly LPS tank would be fine with once a week. 

[mcarroll]

On 3/18/2020 at 6:50 AM, Muffin87 said:

This is the testing routine

It's hard to imagine.

 

SliceGolfer made a nice summary.  Also check out the articles about alkalinity and alkalinity maintenance over on reefkeeping.com and advancedaquarist.com for lots more.

 

Anything you can find by Randy Holmes-Farley or Craig Bingman, for that matter....there is material in other places too, like archive.org.

 

If you don't have some good reefing books, now is the time to get some.

 

Check out....

 

[Muffin87]

On 3/21/2020 at 6:56 AM, mcarroll said:

If you don't have some good reefing books, now is the time to get some.

Thanks for this.

I have some good reefing books, but I haven't been able to find anything on why testing for X is more important than testing for Y or such.

I'd like to be able to prioritise tests.

[SliceGolfer]

There is a lot of info out there, spread across forum posts and videos. I'll outline my test schedule and why:

 

1. Test Alk Wednesday and Saturday. Why? Alk is the element rapidly used by SPS and LPS corals to build their stony skeleton. If Alk rises too fast it can have a negative effect on SPS corals, including death. LPS corals can be affected by rising Alk, but not to the same degree as SPS. On the flip side, Alk depletion to low levels is also a concern, however lowering Alk doesn't necessarily kill corals. Lower Alk can cause corals to fade and lose color or stop growing. My target Alk level is 8.

2. Test Calcium and Magnesium on Saturday. Why? Calcium and Magnesium are used (in conjunction with Alk) to build the stony skeleton. Ca and Mg are consumed at a lesser rate than Alk, and as such testing on a weekly basis is OK. My target Calcium level is 440ppm and Magnesium level is 1440ppm.

3. Test Nitrate and Phosphate on Saturday. Why? Bacteria breaks down nitrate and phosphate into a food source for corals. Depending if nitrate or phosphate are low, I will dose to keep levels detectable by our test kits. I also dose MicroBacter 7 on Sundays to help with the bacteria conversion of N&P to food source. My target nitrate level is 5-10ppm and phosphate level of 0.10ppm.

 

That's it. I don't test for anything else. I don't get caught up in pH testing as my tanks are in my office, and I keep the window closed so I know the gas exchange is probably sub par. I don't do anything to manage pH either. I don't test ammonia or nitrite unless I cannot trace any condition in my tank to any other possibility.

 

I use the following test kits:

Alk - Hanna Checker

Calcium - Hanna Checker

Phosphate - Hanna ULR Checker

Magnesium - Salifert

Nitrate - Red Sea

 

Hope this helps.

[mcarroll]

16 hours ago, Muffin87 said:

I have some good reefing books, but I haven't been able to find anything on why testing for X is more important than testing for Y or such.

I'd like to be able to prioritise tests.

Books will cover the high level issues pretty well...like salinity, supersaturation, etc.   These things are important foundations to understanding alkalinity and the rest.....so don't slouch on the book reading and skip straight to the dosing instructions.  😉

 

Hit the authors and websites I mentioned for info on alkalinity.  Holmes-Farley and Bingman are my two favorites.

 

Arguably, alkalinity is the only one of the three (ca, mg and alk) that really deserves a lot of attention.

 

By comparison with ca and mg, alkalinity...

impacts/is used by way more things...

that have a way deeper impact on the tank...

AND there is far less of it in the water to begin with, so its level varies more extremely than the others. 

 

So focus on alkalinity above all else.  You'll learn the importance of ca and mg along the way....and as I said, there isn't much to them by comparison.

[aclman88]

On 3/24/2020 at 10:16 AM, Muffin87 said:

Thanks for this.

I have some good reefing books, but I haven't been able to find anything on why testing for X is more important than testing for Y or such.

I'd like to be able to prioritise tests.

Just to chime in. Coral skeleton is calcium carbonate. Coral used one part calcium to one part carbonate (we test this using alkalinity). It is a one to one ratio, however, there is way more calcium in the water column. Therefore, alkalinity is depleted more rapidly and changes quicker so it it better to test more often. It’s like if you were to make PBJ sandwiches using equal parts jam and peanut butter each time; you have a small jar of jam (alk) but a huge tub of peanut butter (calcium). Naturally, you want to check your jam more often because it’s going to be used up faster as you make sandwiches. That’s why most people test Alk more often since it is most likely to change and to change a lot of a short amount of time. 

[I'm Batman]

I test Salinity 2-3x a week to make sure my ATO is on point and filters aren’t causing more FW to be added.

 

I test dKh and Ca on Sunday then dose Alk and Ca on Monday.

 

No3 and Po4 right now I’m testing daily.