A tale of two tests + DIY alk

[grassi]

If you own a good titration total hardness kit, like Elos or, better, La Motte you are probably testing your alkalinity pretty close to the real value.

But how to be sure? How to test your test? (naughty)

 

Test kits do a pH endpoint titration. That means that you add acid until the dyes turn color. When the color change you have a solution which is at ph 4,2

 

Now if you are lucky to have a ph probe, you can stick the probe in the solution so you can "test your test". Off course I'm assuming you just calibrated your probe with the 2 acid solutions (whistle)

 

So, due to the nature of the titration you can either test your alk readings or either your ph meter, if you are sure you are reading the alk well.

I really suggest a good kit for this, like La Motte, where you can have readings down to 4 ppm increments. The Elos one is good for fast readings in my opinion.

 

Now the fun part.

At this point if you were smart to buy a lab grade ph probe you can even set up your DIY alk test.

You just need a bottle of 0.1 N Sulfuric acid standard and you can use it as a titrant.

 

Take a sample of your water and stick your ph probe in it. Use a sample container that will easily contain the sample and the ph probe, like 100ml or more

Fill a 5ml syringe with the acid and start dropping some into the sample

You can stop when the ph probe shows 4,2

Now read how much titrant (acid) you had to add

 

Now some math:

if you added 3ml, then multiply it for your acid concentration (in this case 0.1) and then for 50,000 and divide the result by 100 for having the ppm

 

3*0.1*50,000 / 100 = 150 ppm

 

NOTE

I've found some information about this diy method on RC as well, where some source (Randy Holmes Farley) suggested to use standards instead of a ph probe, not being the latter a good gauge. But I think that for a quick reading the ph probe will work as well.

[ReeFit]

i'll take your word for it. So are you for hire to come out and test tanks?

[grassi]

Never put an italian close to a tank and muriatic acid, unless you have to get rid of your in laws :P

[Trautman]

.1n ? what is that?

did you mean .1 M ?

and where did the number 50,000 come from?

[grassi]

Sulfuric Acid Standard 0.1 N in H2O

http://www.coleparmer.com/1/1/22779-sulfuric-acid-0-1-n-standard-solution-1l.html

[Trautman]

huh, odd. i understand molarity, as in m/l but n... hmmm i wonder what it stands for

[grassi]

no idea.. I will try to find out just out of curiosity

[Emerald525]

Please refer to my out of bounds thread and see "Grassi" under definitions. I gave up calculating molarity for Lent.

[jgf86123]

I'm just gonna have to set it up so that Alex comes out to the house once or twice a month an tests my tanks LOL

 

Do you work for frags or beer Alex? LOL

[grassi]

Normality=gram equivalents/liters of the solution

Good thing I bought a couple of Chemistry Books at Powells a few months ago

I wasn't good at chemistry at school. I used to use the burner for tasks that I can't say in this family forum

[grassi]

I work for beer, I'm plenty of frags lol

and for bbq

[Trautman]

haha, well i am a glass blower, so i feel ya man.

[tanktop74]

If you own a good titration total hardness kit, like Elos or, better, La Motte you are probably testing your alkalinity pretty close to the real value.

But how to be sure? How to test your test? (naughty)

 

Test kits do a pH endpoint titration. That means that you add acid until the dyes turn color. When the color change you have a solution which is at ph 4,2

 

Now if you are lucky to have a ph probe, you can stick the probe in the solution so you can "test your test". Off course I'm assuming you just calibrated your probe with the 2 acid solutions (whistle)

 

So, due to the nature of the titration you can either test your alk readings or either your ph meter, if you are sure you are reading the alk well.

I really suggest a good kit for this, like La Motte, where you can have readings down to 4 ppm increments. The Elos one is good for fast readings in my opinion.

 

Now the fun part.

At this point if you were smart to buy a lab grade ph probe you can even set up your DIY alk test.

You just need a bottle of 0.1 N Sulfuric acid standard and you can use it as a titrant.

 

Take a sample of your water and stick your ph probe in it. Use a sample container that will easily contain the sample and the ph probe, like 100ml or more

Fill a 5ml syringe with the acid and start dropping some into the sample

You can stop when the ph probe shows 4,2

Now read how much titrant (acid) you had to add

 

Now some math:

if you added 3ml, then multiply it for your acid concentration (in this case 0.1) and then for 50,000 and divide the result by 100 for having the ppm

 

3*0.1*50,000 / 100 = 150 ppm

 

NOTE

I've found some information about this diy method on RC as well, where some source (Randy Holmes Farley) suggested to use standards instead of a ph probe, not being the latter a good gauge. But I think that for a quick reading the ph probe will work as well.

 

all I can say is I think I was just "Grassied"! Don't know why but that totally just flew over my head!

[madmike]

Ive been testing this way for about the last 6 months. I have a dedicated pinpoint ph meter calibrated with 4 and 7 instead of 7 and 10 for reef. Its easy once you do it a few time, I even have a chart on the wall with all of the math worked out, so I just see how much acid I needed and look at the chart for my DKh.

 

My tank has never looked better now that I know what my true alk is. I previously tested with ELOS and then went to lamotte, but both read a bit off because the endpoint of the color titration is not exactly at 4.2. When you are running an ultra low nutrient system, alk burn becomes a real possibility with sps and alk needs to be kept low but not too low

 

I see people purchasing these hanna alk meters and multiple test kits that add up to a lot of money. For about a $50 used pinpoint monitor and about $30 for a gallon of the acid (thats all I could find it in at grainger, this will last me a lifetime at 5ml per test) you can have a way to test that will outlast any test kit.

[madmike]

all I can say is I think I was just "Grassied"! Don't know why but that totally just flew over my head!

 

Its really easy once you see it done, all the math turns people away but a chart can be made easily so no math is needed.

 

Here is a link to the acid that will work

http://www.grainger.com/Grainger/Sulfuric-Acid-4YNA6?Pid=search

(only hiccup with ordering from grainger is the acid HAS to be sent to a business, I tried to get it sent to my house but the mnf refused to ship unless it went to a business)

[Emerald525]

Its really easy once you see it done, all the math turns people away but a chart can be made easily so no math is needed.

 

Here is a link to the acid that will work

http://www.grainger.com/Grainger/Sulfuric-Acid-4YNA6?Pid=search

(only hiccup with ordering from grainger is the acid HAS to be sent to a business, I tried to get it sent to my house but the mnf refused to ship unless it went to a business)

 

While you're at it why don't you figure out that dopamine drip for me and I may need you to calculate that prostaglandin drip! I heart pharmacists!(clap)(clap)

 

Send it to Ca2OR corals....(whistle)

[grassi]

So I'm not the only crazy one!

Mike, I'm running an ultra low nutrient system and since I went that way and my frags became colonies I noticed an incredible growth on the tips, but recession on the base. So I'm dealing with alk, trying to know better the ionic balance of my tank. I use both elos and la motte, but I'm gonna try this way too.

Where do you keep your alk, calcium and mag?

[BrianB]

Normality=gram equivalents/liters of the solution

Good thing I bought a couple of Chemistry Books at Powells a few months ago

I wasn't good at chemistry at school. I used to use the burner for tasks that I can't say in this family forum

 

 

 

So that's where the name Grassi came from lol.

[madmike]

I heart pharmacists!

 

awwwwww, Its nice to be loved

 

Where do you keep your alk, calcium and mag?

 

I find that alk is the SINGLE most important parameter that MUST be kept stable to have a successful sps tank. I keep alk between 8-9, usually 8.5. My mag seems to be pretty stable using reef crystals and I only have to dose every month or two with a few cups of mag chloride/sulfate mix. I like to keep my calcium at around 400-430 but I have been going through a growth spurt lately and am having trouble keeping it above 375. I just bumped my auto dosing up to 1500ml daily from 1200ml daily. Just for reference I am only using about 400ml daily of alk.

[madmike]

I noticed an incredible growth on the tips, but recession on the base

 

That sounds odd, recession from the base is usually a flow, light shading, or dare I say aefw (scary) ... I know for a fact that these are floating around in our area and some very prominent members have them :(

[grassi]

I dose 200 ml of each and 1ml of mg, but I started the balling light only a few weeks ago and I'm still trying to find the right spot. Yes, I test every single day since then

As for the acros, I'm investigating the problem. I'm running since actinics since 2 weeks. My fixture burned 2 ballasts in the last 2 weeks :(

Flow has always been the same in that tank (about 17 months old) and I had great results.

As for aefw (see kim, I'm not the only one using acronysms!) I'll do the test suggested by Melev.

Thank you

[grassi]

I just did the test on a couple of colonies and it was negative.

So I don't think that the problem is related to aefw phevvvvv

I didn't see any bite marks and the color of the colony is still great.

I will do the test again tomorrow on a different colony to be 100% sure and I will prepare a slide to put under the scope so I can sleep better

 

It could just be that my system went too fast and too low on nutrients while the colonies were growing a lot. I switched to a different food, so I can daily and constantly feed.

Also, tuning the doser could have played a role on this, because I have some fluctuations on the alk, ca and mg side. I'll post some pics to show what I'm talking about.

Going a little bit out of topic, sorry :(

[racefan]

Never put an italian close to a tank and muriatic acid' date=' unless you have to [b']get rid of your in laws[/b] :P

 

PM me to set up an appt.(threaten)(plotting)