Alk dosing

[RobbieMaynard]

Hello - I have a 5 month old 40 gal aio. Parameters below. I’ve been testing every week to 10 days and my Alk fluctuates between 6.8-6.9 DkH. All other parameters are reasonable. I do 20-15% water changes every 2 weeks using reef crystals. Mostly LPS with some ricordea and Zoas. No SPS. Looking to get a little more growth out of the corals so I’m thinking of raising Alk to 8-8.5. Don’t have a dosing pump yet but Putting money aside for one. Any thoughts on what I can do to bring the Alk up. Do I need to do a 2 part if other parameters are reasonable? Sodium bicarbonate? Would greatly appreciate any advice/input. Especially if someone can point me in right direction to do more research. Thanks in advance.

Nitrate 12.8ppm
Phosphate: 0.05 ppm
Alk: 6.9 DkH
Calcium: 430
Mag: 1350
PH: 8
Salinity:35ppm

 

[Gtinnel]

The most common methods to raise alkalinity are dosing 2 part (technically its 3 part) or something similar, using Kalkwasser, or using a calcium reactor.
The only one I’ve ever personally used is 2 part dosing, and I use solutions that I make from sodium bicarbonate (which I bake to convert to sodium carbonate), then for the other parts I use chemicals I buy from Bulk Reef Supply.

You can dose just the alkalinity part to get your level where you want it, but once you are just dosing to replace what is consumed in the tank you should be dosing both parts (alk/cal) at essentially the same rate. If you go with the diy 2 part then wether you dose sodium bicarbonate (baking soda) or sodium carbonate (soda ash or washing soda) will be based upon if you need or want a boost in your pH.

Our resident chemist has an article he wrote about making your own 2 part.

https://reefkeeping.com/issues/2006-02/rhf/index.php

 

[EeyoreIsMySpiritAnimal]

You can try doing large water changes. IORC has a higher alk usually between 9 and 12. Test your freshly mixed SW and calculate how much water you'd need to replace to raise the tank alk by 1dkh.

 

[Gtinnel]

You can try doing large water changes. IORC has a higher alk usually between 9 and 12. Test your freshly mixed SW and calculate how much water you'd need to replace to raise the tank alk by 1dkh.

They would need to change at least 1/4 of their tanks water and it will also effect their other parameters (although possibly for the better).

IMO water changes to replenish major elements is a waste of money, when there are cheap chemicals you can buy to replenish them. Just relying on water changes is not a reasonable long term solution when/if the demand in their tank gets to an even moderate amount.

In a thread Randy once discussed how much water would have to be changed to keep levels stable and it was insane how much it took long term. If they need to start dosing eventually, I thinks it’s best to just go ahead and learn what works best for them and how to successfully do it.

 

[RobbieMaynard]

The most common methods to raise alkalinity are dosing 2 part (technically its 3 part) or something similar, using Kalkwasser, or using a calcium reactor.
The only one I’ve ever personally used is 2 part dosing, and I use solutions that I make from sodium bicarbonate (which I bake to convert to sodium carbonate), then for the other parts I use chemicals I buy from Bulk Reef Supply.

You can dose just the alkalinity part to get your level where you want it, but once you are just dosing to replace what is consumed in the tank you should be dosing both parts (alk/cal) at essentially the same rate. If you go with the diy 2 part then wether you dose sodium bicarbonate (baking soda) or sodium carbonate (soda ash or washing soda) will be based upon if you need or want a boost in your pH.

Our resident chemist has an article he wrote about making your own 2 part.

https://reefkeeping.com/issues/2006-02/rhf/index.php

Appreciate the guidance. I’m checking out the article.

 

[Gtinnel]

This BRS video gives some of the basic info on 2 part also

 

[kdx7214]

I've been using the stuff from this link:

http://reefkeeping.com/issues/2006-02/rhf/index.php

 

[EeyoreIsMySpiritAnimal]

They would need to change at least 1/4 of their tanks water and it will also effect their other parameters (although possibly for the better).

IMO water changes to replenish major elements is a waste of money, when there are cheap chemicals you can buy to replenish them. Just relying on water changes is not a reasonable long term solution when/if the demand in their tank gets to an even moderate amount.

In a thread Randy once discussed how much water would have to be changed to keep levels stable and it was insane how much it took long term. If they need to start dosing eventually, I thinks it’s best to just go ahead and learn what works best for them and how to successfully do it.

I understand that, but he was asking for options... It's a 40 gallon tank so 10 gallons wouldn't be that difficult. Since he's already using a high alk salt, I figured it was worth mentioning.

 

[RobbieMaynard]

Thanks Erin and Gtinnel. I’ve been doing between 8-10 gallon water changes every 2 weeks. You definitely gave me some ideas. I can try switching to weekly changes and then test the Alk in my fresh saltwater before the change and then I’ll test Alk consecutively each day after the water change. That should help me get a better idea of potential consumption. Appreciate the advice.