New salt with lower dkh

brownjoshua475 · Jan 5, 2020

Hello there I was wondering I'm switching from fritz blue box to tropic marin reef pro salt. I just tested the new batch the tropic marin at 35ppt and the dkh is 7.5 and my current tank is at 9.3 dkh. I was wondering how bad will it drop my dkh if I add the new batch.

vetteguy53081 · Jan 5, 2020

Which Marin ? I use the TM Actif and dkh is 8.5. I belive the pro runs higher range also

brownjoshua475 · Jan 5, 2020

vetteguy53081 said:
Which Marin ? I use the TM Actif and dkh is 8.5. I belive the pro runs higher range also

Tropic marin Reef Pro

brownjoshua475 · Jan 5, 2020

vetteguy53081 said:
Which Marin ? I use the TM Actif and dkh is 8.5. I belive the pro runs higher range also

Usually the pro runs lower dkh with higher calcium and magnesium

Chefwheredyougo · Jan 5, 2020

I think it depends on the water change percentage.

vetteguy53081 · Jan 5, 2020

According to my old bucket for pro> To maintain the alkalinity in a 7-8° dKH range.

brownjoshua475 · Jan 5, 2020

Chefwheredyougo said:
I think it depends on the water change percentage.

I usually do a 5 gallon water change in a 32 gallon biocube

brownjoshua475 · Jan 5, 2020

vetteguy53081 said:
According to my old bucket for pro> To maintain the alkalinity in a 7-8° dKH range.

Yes that's what I'm getting when I test dkh. In the new batch of water I'm making My test is 7.5 dkh

vetteguy53081 · Jan 5, 2020

brownjoshua475 said:
I usually do a 5 gallon water change in a 32 gallon biocube

What test kit are you using to measure DKH ?? I would take a sample to a trusted LFS and have them check for you for comparison and also verify accuracy of your test kit. Sounds a little low for TM salt

brownjoshua475 · Jan 5, 2020

vetteguy53081 said:
What test kit are you using to measure DKH ?? I would take a sample to a trusted LFS and have them check for you for comparison and also verify accuracy of your test kit. Sounds a little low for TM salt

I use hanna checker and salifert

ihavecrabs · Jan 5, 2020

You can always dose alkalinity to bring it into the correct range before performing the water change. Many people lower the alkalinity in IO with acid before doing WC with it because it sits around 10dkh.

I just choose not to perform water changes

brownjoshua475 · Jan 5, 2020

ihavecrabs said:
You can always dose alkalinity to bring it into the correct range before performing the water change. Many people lower the alkalinity in IO with acid before doing WC with it because it sits around 10dkh.

I just choose not to perform water changes

Ya I know I was wondering how much it would drop my current dkh in my display if I did a water change with 7.5 and display is 9.3

Deephouse_jedi · Jan 5, 2020

brownjoshua475 said:
Ya I know I was wondering how much it would drop my current dkh in my display if I did a water change with 7.5 and display is 9.3

I don't think it would drop it too much. Maybe 8.8 if I had to guess. If it was a 50% change it would be 8.4. Since it's only a 15% wc it might only drop to 8.8-9.0.

Duffer · Jan 5, 2020

I use tropoc Marin pro and the alk is what I usually get...you can dose some alk in the new mix to match you tank alk and you should be fine.

Btw good choice on switching away from fritz

SDK · Jan 5, 2020

You should be fine for this water change. I use TM Pro Reef and add 2ml Red Sea liquid Alk to my change water while it’s mixing.

You just need to figure out the proper dose once, then repeat it with each WC.

nereefpat · Jan 5, 2020

brownjoshua475 said:
Ya I know I was wondering how much it would drop my current dkh in my display if I did a water change with 7.5 and display is 9.3

The calculation:

7.5 x 5 gallons = 37.5
9.3 x 27 gallons = 251.1
251.1+37.5=288.6
288.6÷ 32 gallons = 9.02 dKH

The final number will be a little lower, assuming you don't actually have quite 32 gallons of water considering displacement from rock etc.

Joedubyk · Jan 5, 2020

vetteguy53081 said:
What test kit are you using to measure DKH ?? I would take a sample to a trusted LFS and have them check for you for comparison and also verify accuracy of your test kit. Sounds a little low for TM salt

My tropic marin mixes in the 7 range as well.
I would not worry about the ALK swing with water changes...

Joedubyk · Jan 5, 2020

nereefpat said:
The calculation:

7.5 x 5 gallons = 37.5
9.3 x 27 gallons = 251.1
251.1+37.5=288.6
288.6÷ 32 gallons = 9.02 dKH

The final number will be a little lower, assuming you don't actually have quite 32 gallons of water considering displacement from rock etc.

Great post- simple math. It's not something to worry about IME.