Raising Alkalinity?

[kathya0321]

I just took some readings:

8.0 PH
10 ppm Nitrate
0.031 Phosphate
7.84 DKH

My question is that my Alk dropped from 8.064 DKH in 2 days, I did a 10% water change on my 16 gal Bio Cube 2 days ago. I would like to raise my DKH to 9, but afraid of my PH dropping any lower. Thoughts?

 

[X-37B]

Raising dkh will not lower ph.
Why do you want a dkh of 9?
8 is fine unless your new salt is 9 then that makes sense.
Dosing 2 part will keep your dkh stable also.

 

[saltyfins]

Raising dkh will not lower ph.
Why do you want a dkh of 9?
8 is fine unless your new salt is 9 then that makes sense.
Dosing 2 part will keep your dkh stable also.

what 2 part do you suggest?

 

[gbroadbridge]

I just took some readings:

8.0 PH
10 ppm Nitrate
0.031 Phosphate
7.84 DKH

My question is that my Alk dropped from 8.064 DKH in 2 days, I did a 10% water change on my 16 gal Bio Cube 2 days ago. I would like to raise my DKH to 9, but afraid of my PH dropping any lower. Thoughts?

There aren't many hobby measurement instruments that can accurately measure a drop from 8 .0 to 7.8 as most are only accurate to +- 0.3.

Unless your drop is consistent over the course of a week or more, it is most likely a measurement error.

What instrument did you use?

Regards
Graham

 

[kathya0321]

There aren't many hobby measurement instruments that can accurately measure a drop from 8 .0 to 7.8 as most are only accurate to +- 0.3.

Unless your drop is consistent over the course of a week or more, it is most likely a measurement error.

What instrument did you use?

Regards
Graham

I use a Hanna Checker for Alkalinity.

 

[mdb_talon]

There aren't many hobby measurement instruments that can accurately measure a drop from 8 .0 to 7.8 as most are only accurate to +- 0.3.

Unless your drop is consistent over the course of a week or more, it is most likely a measurement error.

What instrument did you use?

Regards
Graham

This. The drop you mention is for practical purposes the same reading. The checker itself has a margin of error when you do things perfect. Factor in whether you used 10.0000 ml of water and 1.0000 ml of reagent both times and the margin of error increases even further. Measure it daily or every couple days for a week or so and see what the change is over that time. Then if needed start planning out how you want to dose.

 

[X-37B]

what 2 part do you suggest?

I use ESV 2 part.

 

[gbroadbridge]

I use a Hanna Checker for Alkalinity.

A lot of people do.

Bear in mind the specifications.

At 8 dKh, the accuracy is +- 0.4 dKh, even if you managed to use an exact sample size of 10ml, and 1 ml of reagent,
and everything was at 25 degrees celcius both times.

It's a useful tool for mapping trends over a reasonable period of time, but needs to be taken with a grain of salt if you compare two measurements taken over a couple of days.

Also, keep in mind that when you open a new bottle of reagent, there can be a sudden jump up or down of 0.5 dKh or more compared to the previous bottle.

Regards
Graham.