measuring effluent dkh

[jallen1964]

How can I measure 30-40 dkh using a salifert test kit?

[marsh]

I believe using Salifert Alk kit each 1 ml of reagent is equivalent to 16 dKH....assuming you use 4 ml effluent. You will require ~ 2 -2.5 cc to neutralize to your endpoint.

Two methods:

1. Total Volume Remaining (TVR) (Chart Method)= read off the volume remaining in the last syringe from the bottom of the plunger. Look this value up on the supplied chart. Add #syringe fulls*16 + dKH chart value

2. Total Volume Used (TVU) = calculate the Total Volume Used on the last syringe 1-(TVR) and add result to n* 1 ml then multple sum by 16. n is the the number of syringes completely emptied.
TVU = ((1-TVR last syringe ml) + n*1 ml)
TVU * 16 = x dKH

For example ....bottom of plunger reads 0.48 ml on the last syringe. You had emptied 2 other syringes

1. TVR = 0.48.... look at chart 0.48 TVR ...8.3 dKH
2*16 + 8.3 = 40.3 dKH

2. TVU = ((1-0.48) + 2*1ml) = 2.52 ml
Multiplier = 16
2.52 * 16 = 40.32 dKH

[mattboy]

Use the low resolution mode (2ml sample, 1 drop dye), you'll probably only go through one syringe of acid.

[jdieck]

Yes use the low resolution or dilute the sample 50/50 with distilled or RO/DI water and test as usual, multiply the result by 2

[jallen1964]

If I use your method Jd, won't I be limited to measure a max of 32 dkh? I like the idea of not using a lot of acid.

[jdieck]

<a href=showthread.php?s=&postid=9748533#post9748533 target=_blank>Originally posted</a> by jallen1964
If I use your method Jd, won't I be limited to measure a max of 32 dkh? I like the idea of not using a lot of acid.
If you either dilute by half or use the low resolution you will use half the acid than if you would if using the normal resolution mode with no dilution.
The only difference will be that if you dilute you will be using the normal amount of powder (one measuring spoon) instead of half measuring spoon with the low resolution.
The other difference is that diluting you will have a bit better resolution than in the low resolution mode. If you dilute to 50/50 do not forget to multiply the result by two.

[jallen1964]

Thanks, I'll give it a try.

[jnfallon]

powder? no powder in my alk kit. do I have the old or the new?

[marsh]

Yes, Jd has the Salifert Ca++/Mg++ kits confused with the Salifert KH/Alk kit. The KH/Alk kit includes the KH-IND indicator dye of which 2 drops are added for high res or 4 ml 50/50 low res dilution (1 drop for 2ml low res) followed by KH titration acid.

[jdieck]

<a href=showthread.php?s=&postid=9751684#post9751684 target=_blank>Originally posted</a> by jnfallon
powder? no powder in my alk kit. do I have the old or the new?
Forget about the powder, everything I mentioned apply. Sorry. I was just in the previous post responding to a question about the Seachem Calcium kit and got crosswired.:crazy1:

[Billybeau1]

doh !!!! Hate when that happens. :lol:

jd..... your doing a fine job. Helping lots of people. :thumbsup:

[jdieck]

I do not know how you keep track Billy, it is just confusing, sometimes I have to read the whole thread again to get back in track.