Mr. Fosi's drilled 20H

[Rockfish]

14K Phoenix is the bomb-biggity.

 

just ordered one.....i'm glad to hear positive things about them...i was going to go with a megachrome but the Phoenix was on sale for 55 bucks

[Mr. Fosi]

Did you see my super spiffy Phoenix 14K thread?

[airman_verde04]

 

(singing) THE CIRCLE OF LIFE!!!!!!

[Mr. Fosi]

^ That's pretty funny.

 

So I bought a pH probe off ebay and it should be here next week. Now I need to work out a method for testing alkalinity without a test kit. There's a method in my Handbook of Limnological Methods but I haven't really looked into it. I'll need an acid but once I work it out, it'll be a lot simpler and cheaper than Salifert kits.

 

I also got an order from BulkReefSupply.com last week; one of the 2-gallon refill kits. I didn't feel like making up a full gallon for each of the parts (Ca, Alk and Mg) so I split each of them up into 5x1 L packets (plus a little).

 

In the packets that came to me there was:

 

NaHCO3 = 386.7 g

CaCl = 376.4 g

MgCl + MgSO4 = 255.2 g

 

To mix up 1 L of each solution I used:

 

NaHCO3 = 66.9 g

CaCl = 65.1 g

MgCl + MgSO4 = 44.2 g

 

Even though I worked fast, the CaCl managed to absorb a little more than 1 g by the time I finished weighing it out and splitting it up. That's not bad though... Only 0.3% of the total so I'm not worried about it. It can absorb as much water as it wants now because it was weighed accurately while it was still anhydrous. It had a neat little endothermic reaction as I mixed it up too, complete with a nice fresh smell.

 

Also, I forgot to test the last two days so I also didn't dose. I tested tonight and came back with alk = 6.85, down from 10.1 on the 26th. That means that my tank is chewing through 1.63 dKH per day.

 

I did a waterchange with 5.6 gal of 10 dKH water and I'll test tomorrow morning. I am sure I will need to dose it up but that's fine. I'll start with the new solutions tomorrow and see how different they are from B-Ionic (I've been dosing just under 15 mL alk per day).

 

So the moral of the story is that you don't need a lot of SPS and LPS to drag down your alk... Boy, I really need to work out a mechanism to dose several mL per day of alk.

[Mr. Fosi]

My pH probe came today. The ebay seller said that it would arrive next week but they were thankfully wrong.

 

It looks as though it is just as accurate and holds a calibration just as well as the two probes I tested at the lab and it cost me less than $25 shipped. Here's a link to the auction in case anyone cares.

 

Also, I finished the written portion of my comprehensive exam today so I will have a little time to work out the alkalinity method over the next few days.

[airman_verde04]

My pH probe came today. The ebay seller said that it would arrive next week but they were thankfully wrong.

 

It looks as though it is just as accurate and holds a calibration just as well as the two probes I tested at the lab and it cost me less than $25 shipped. Here's a link to the auction in case anyone cares.

 

Also, I finished the written portion of my comprehensive exam today so I will have a little time to work out the alkalinity method over the next few days.

 

So what you are saying is your grad school projects basiclly revole around issues and science Involed in reef keeping. So in turn your able to study using some of your own personal testing tools, and those usc provides you with at your lab, Ergo; making you a super smart reef nerd.. Did I get that right?

[Urchinhead]

Hey mate-

 

For what its worth odds are that stuff I sent over to you is what's chowing down on your CaCO3. They are all pretty fast growers when happy and my own dosing regimen went down by about 5 ml on the Ca side and 10 ml on the CaCO3 side after they left my tank...

[Mr. Fosi]

So what you are saying is your grad school projects basiclly revole around issues and science Involed in reef keeping.

 

No so much... I am working on microbial interactions (microalgae and bacteria) which isn't exactly reef-keeping but a lot of the techniques I have learned can be used at some level in the hobby.

 

... my own dosing regimen went down by about 5 ml on the Ca side and 10 ml on the CaCO3 side after they left my tank...

 

That's an interesting bit of data. I'm not sure how much mine has gone up, but it has certainly gone up. In light of that, her are a couple selected pics.

 

 

 

 

 

[Mr. Fosi]

I decided to try for a couple macro shots of the micromussa.

 

 

 

[Mr. Fosi]

I have been poking through my Handbook of Limnological Methods. There is an alkalinity method listed and the short form is this:

 

- 3 mL concentrated H₂SO₄ diluted to 1 L (using CO₂-free FW) to yield a ~0.1 N stock soln.

- 200 mL stock soln diluted to 1 L to yield a ~0.02 N standard soln (needs to be standardized against CaCO₃ to be accurate).

 

The book recommends that you analyze a sample of 100 mL (less could be used if you aren't using indicator dyes) and it also gives the methods for doing the titration with indicator dyes (like a standard hobby test kit) and with a pH probe (what I intend to do). Assuming you use a properly calibrated probe, it is much more accurate and precise than the dye method.

 

So I got to thinking, "I wonder what acid normality Salifert uses in their kits?" Well, the equations for calculating total alkalinity (the value you report when someone asks what your alk is) are also given:

 

Alk_T = (B*N*50000)/V

 

Alk_T = total alkalinity in mg CaCO₃ L^-1

B = Volume (mL) of titrant added to reach pH 4.5 (the end-point for bicarbonate; HCO₃^-)

N = Acid normality

V = Sample volume (mL)

 

I rearranged the equation to solve for N (normality):

 

(Alk_T*V)/(50000*B ) = N

 

And plugged in the values I got when I tested this morning:

 

Alk_T = 9.6 dKH (3.43 meq/L)

V = 4 mL

B = 0.33 mL (take note that when you bring the plunger up to 1 mL the liquid only reaches up to ~0.73 mL)

 

But alas! The Alk_T is in the wrong units! dKH and meq/L are not appropriate for use in this equation, Alk_T must be converted into mg CaCO₃/L.

 

Never fear, the conversion is simple: Just multiply dKH by 17.86 or meq/L by 50.04.

 

Alk_T = 171.46 mg CaCO₃/L

 

Plug that value into the rearranged equation above and you get:

 

N = 0.0416

 

So then, Salifert is using a higher concentration of acid than my methods handbook suggests (0.02 N). This means that I may be able to mix up my own acid titrant, standardize it against NaCO₃ (dry baking soda) and I will have a homemade test kit that is more precise and accurate than the commercial kits.

 

Theoretically, I don't need to use H₂SO₄ and could use virtually any strong acid so long as I mixed it up to ~0.02 N and ran a standard curve. Luckily, I know of someone who can (and will) lend me 3 mL of concentrated H₂SO₄ to try this out.

 

If it works, I will never buy another alk kit again and I'll get started on the Ca and Mg analysis as well.

[spanko]

Sorry if I missed it previously but what is this sir????

 

[Mr. Fosi]

That's a purple encrusting monti w/blue polyps. It is still a bit bleached form shipping and it's previous digs but it is slowly coloring back up.

[Mr. Fosi]

It seems to me that HCl should work for this method as well, though it is monoprotic acid.

 

I wonder what the concentration of muratic acid is... The type you can buy by the gallon at HD or other home-improvement stores.

[Needreefunds]

Oh, just buy the test kits. They aren't that expensive.

 

 

Sorry I-man. I had to.

 

Just trying to give ya a chuckle.

 

Following along and curious to see how you make out there.

 

Sweet micro Isaac. While it may seem somewhat dull at first glance, a closer look reveals a healthy colony with beautiful subtle patches of rainbow color and glow. Great pick up there Sir.

 

 

DIY FTW IMO

[jjjo]

I decided to try for a couple macro shots of the micromussa.

 

 

 

 

looks good!

[lakshwadeep]

HCl should be fine with determining carbonate hardness, which includes both the bicarbonate and carbonate ions. You should also check pool supply stores, but I'm not sure if muriatic acid will be 12 M. I did a similar test in my quantitative analysis lab where we determined the Calcium concentration using EDTA titration. I'll try to find more info on what kinds of indicators you should be using.

[Mr. Fosi]

Ca needs to be done with EDTA because of it's chelation ability I believe.

 

The alkalinity indicators are: Pheolpthalein & methyl orange or bromcresol green-methyl red.

 

The general hardness indicator is: Eriochrome black T

 

The Ca indicator is: Murexide

 

I don't plan to use an indicator for the alk since it can be easily done with my pH meter + probe. I'll need to recalibrate the probe for 4-7 but that is easy (I have the buffer solutions).

 

The Ca and general hardness tests (that I have methods for) require the indicator dyes.

[Mr. Fosi]

I was going to use some DIY casting acrylic but I got impatient and decided that I would rather use epoxy because it sets in 5-8 minutes and my DIY acrylic casting material would take at least 12 hours (estimate based on previous projects). Plus, I wasn't sure how I was going to cast the acrylic because the solvents cause problems... I would have had to use something like foil to line the molds.

 

So here are some pics of what I did this evening.

 

 

 

 

 

 

 

The wooden mold holes were cut with a 1" auger bit and I covered them in seran-wrap so the wood wouldn't get caked up. The epoxy will bond fairly well to it so I had to make sure to separate it before it setup too much. I mixed and applied the epoxy with toothpicks. I held the magnets in the holes with other magnets on the underside of the block.

 

Right now the epoxy is hard-ish to the touch and the back end (that will sit against the glass) isn't as smooth as the tops (I just couldn't leave them alone ) but I think this is a good first attempt. I need to add a little bit to the edges of the magnets just to be sure that they are 100% covered. I'm going to wait until tomorrow evening for a water test to ensure it fully cures.

 

I also decided to coat the cheap-o 1" ceramic magnets I found at Michael's. They aren't strong enough for a rack but they may work as individual mag-plugs (not for SPS though ). We'll see how they do once I have a set fully coated-cured (tomorrow hopefully).

 

The magnets are 1"x1/8" N52 neodymium magnets.

[travisurfer]

Nothing beats Neodymium magnets...nothing...

[spanko]

Nothing beats Neodymium magnets...nothing...

 

 

+1 Rare earth magnets are the best!

[Mr. Fosi]

 

 

 

 

 

The el-cheapo 1" ceramic magnets from Michaels coated well and are strong enough to hold a frag a piece.

[Mr. Fosi]

I borrowed a copy of Standard Methods for Examination of Water and Wastewater from USC's library for the purpose of clarifying some of the finer points of the total alkalinity method outlined in my limnological handbook.

 

In particular, I was conerned with how to standardize the acid solution, since this is the key part of the analysis. If you look at my previous post, I metion standardizing against CaCO₃. Something didn't sit right after I posted that and that's a good thing because it was incorrect. CaCO₃ isn't very soluble in water (unless the water is a low pH).

 

Instead, I need to standardize against something more soluble, such as Na₂CO₃ (a.k.a. Sodium carbonate or washing soda). This is not the same as baking soda (sodium bicarbonate) whose formula is NaHCO₃, however, baking soda can be transformed into washing soda by heating it.

 

If my stoichiometry is correct:

 

2NaHCO₃ + heat => Na₂CO₃ + CO₂ + H₂O

 

By "heating it" I mean baking it at >250F for >1 hr. The amount of time partially depends on how much you plan to heat at a time and partially on how long it takes to drive off the water and carbon dioxide. Once it has been baked, it needs to be cooled in a desiccator to ensure that it doesn't re-absorb any water.

 

The standard 0.05N Na₂CO₃ solution (that you titrate the acid solution against) is made by adding 2.5g anhydrous Na₂CO₃ to a 1L volumetric flask and adding water (distilled or RO) to the 1L line. The solution is good for no longer than a week.

 

The standardization for a 0.1N acid solution is to be done like this:

 

"b. Standard sulfuric acid or hydrochloric acid, 0.10N: Standardize against 40.00 mL 0.05N Na₂CO₃ solution, with about 60.00 mL water, in a beaker by titrating potentiometrically to a pH of about 5. Lift out electrodes, rinse into the same beaker, and boil gently for 3-5 minutes under a watch glass cover. Cool to room temperature, rinse cover glass into beaker, and finish titrating to the pH inflection point (4.5). Calculate normality:

 

N = AB/53C

 

N = Normality (of the acid solution)

A = g Na₂CO₃ weighed into 1-L flask

B = mL Na₂CO₃ solution taken for titration

C = mL acid used

 

"Use meaured normality in calculations or adjust to 0.1000N; 1 mL 0.1000N solution = 5.00 mg CaCO₃."

 

This is a little different than is given in my limnological analysis handbook. In that text, they advocate using a 0.02N acid solution. There is a method in Standard Methods for that as well:

 

"c. Standard sulfuric acid or hydrochloric acid, 0.02N: Dilute 200.0 mL 0.1N standard acid to 1000 mL with distilled or deionized water. Standardize by potentiometric titration of 15.00 mL 0.05 Na₂CO₃ according to the procedure [above]; 1 mL = 1.00 mg CaCO₃"

 

I still have some questions... I don't quite understand what they mean when they say "Standardize against 40.00 mL 0.05N Na₂CO₃ solution, with about 60.00 mL water, in a beaker..." So that is 40 mL of the standard solution in one beaker and 60 mL water in another? For what purpose? Rinsing? Are they assuming that the analyst will be using a pH probe with a separate reference electrode? Or do they mean add 40 mL to 60 mL? That would change the normality and screw up the method.

 

It seems as though they are assuming that the investigator will be using a pH electrode with a separate reference electrode but I'm not sure.

 

Also, my (and lak's) assertion that HCl should also work for this method is supported by what I see in Standard Methods. The acids are interchangeable so long as they are the proper N.

 

I'm getting there! I've already made up the stock 0.2N and 0.02N H₂SO₄ solutions. I have some lab-grade NaHCO₃ on hand and I will probably bake it for 4 hours tomorrow. That just leaves the bit of confusion regarding the dual-beaker "potentiometric" part of the method.

[Lalani]

I'm just here for the pretty pics.

[airman_verde04]

No so much... I am working on microbial interactions (microalgae and bacteria) which isn't exactly reef-keeping but a lot of the techniques I have learned can be used at some level in the hobby.

 

So you would be intertested in som samples of ramdon native plants from Qatar? I'm sure I could bag them up and bring them home with me... I could even figure out a way to send them through the mail. haha.. and if some crazy ilness spreads arcoss the US, and its based by a bacteria from Qatar.. I had nothing to do with it. HAHA

[Mr. Fosi]

I'm just here for the pretty pics.

 

And you have nothing to say about my DIY mag-rack?

 

So you would be intertested in som samples of ramdon native plants from Qatar?

 

Maybe if I had the time to analyze them!

 

About the alk method: Further reading indicates that the method I transcribed above does assume that the analyst will have a pH electrode + reference electrode. This is not needed in glass internal reference probes, the probe type that I own and that can be found in most labs.

 

Therefore, the method could be re-written leaving out the extra 60 mL water instruction.

 

"b. Standard sulfuric acid or hydrochloric acid, 0.10N: Standardize against 40.00 mL 0.05N Na₂CO₃ solution in a beaker by titrating potentiometrically to a pH of about 5..."

 

Well, tomorrow I will bake several grams of sodium bicarbonate at 300F for no less than 2 hours. Once that is done, I will make up a standard solution and set about standardizing the acid titrant.

 

Once I have the acid standardized, I will make some measurements with it and compare them to what I get off a Salifert kit. I may try another commercial/laboratory kit for alk to confirm the results as well.