dkH question

[sumpreef]

I have a 40gallon display with about 10gallon of water volume in the sump for a total of 50gallon systems with about 10 or so frags of primarily soft LPS corals. Tank has been set up for about 2-3 months and doing well. All corals are doing well. A pair of clowns in the tank. Diatoms but no other serious algae. No Coraline algae. IO reef crystal mix for salt.

Always used the API test kit to start and measured around 10dkh.. Recently changed test kit to Hanna and it measures around 7.2 and now 6.8. Calcium(Aquaforest) around 420 and Mg (salifert) around 1380. Retested with API and it measures 9 while the Hanna measures 6.8. Quite a bit different and unsure which is the accurate real representation of the tank.

The secondary question is when should I start dosing? If so, what would you recommend? Tropic Marin All for Reef or BRS two part since I can dose things independently as Calcium is not depleted? Thank you!

 

[get-salty]

API is fine when starting up a new setup while ALK is the most important element to test, id use Hanna or Salifert going forward.

Your mg and cal results looks spot on.

You only dose only when things are being taken up by your corals. If your #s are within range, you do not need to dose.

Having a ~40gal.. to me, a regular WC can replenish most of the elements.

 

[Gumbies R Us]

I agree that Salifert, Hanna or even RedSea kits should be something you invest in

 

[sumpreef]

Yeah I have both the Hanna and the api for alk. They are both giving different results so not sure which one is the true result. Hanna says 6.8 and api says 9. Reef crystals IO theoretically mixes to a dkh of around 10-12. Assuming it wasn’t an inconsistent batch and assuming I trust Hana over api., I’m just surprised my dkh went down that much with just soft corals.

 

[get-salty]

yes, i agree that alk is pretty high on IO salt.

Are you using an auto top off system or manual top off?

 

[sumpreef]

ATO and salinity is spot on at 1.025 with the milwakee checker and calibrated refractometer

 

[Randy Holmes-Farley]

While either or both may be off, a new Hanna is more likely to be accurate.

Try the Hanna in the new salt water.

Assuming alk is below 7 dKH, I’d dose to get it into the 7-11 dKH range.

Do you have a plan of what to dose for alk and calcium going forward?

There are many good choices.

 

[sumpreef]

Thank you all for your helpful suggestions and tips.

I had pre-mixed a bunch of salt water about a week and a half ago. I realize that alkalinity can slowly decrease overtime but as you have suggested I checked the saltwater mix that I had made previously and that measures are on 9.7 on the Hanna checker. So it does appear that my tank is actively using DKH. I was thinking about using the BRS two part to dose as it gives me flexibility in selecting what is needed to be dosed pending results. Thoughts and suggestions?

 

[sumpreef]

Specifically this one

2-Part Pharma Calcium & Alkalinity Starter Package

Start Replenishing Calcium and Alkalinity in your Reef Tank! Keep your corals growing with the BRS 2-Part Calcium & Alkalinity Starter Package. The kit includes everything to make one gallon of calcium, alkalinity, and magnesium and to start daily dosing, it even includes mixing jugs, dispensing...

www.bulkreefsupply.com

 

[Randy Holmes-Farley]

They use my recipe and it’s a fine way to go, but I’d plan to dose both parts equally based on alk. Calcium moves to slowly to be used to jigger doses based on frequent testing.

This thread suggests the best way to use these materials:

DIY Balling Method Recipe

The Balling DIY supplement recipe utilize a 1:1:1 dosing ratio to maintain proper alkalinity. For instance, if you require 50 mL of the alkalinity solution, you should also add 50 mL of Calcium and Balling. Alkalinity (Choose One) : Option 1: Soda Ash Add 375 g soda ash to enough RO/DI to...

www.reef2reef.com

 

[sumpreef]

Thank you. Appreciate the link. Will review it in depth tonight. But pardon my curiosity if the calcium levels are already at acceptable levels, why do we need to dose calcium when we aredosing for alkalinity?

 

[Randy Holmes-Farley]

Thank you. Appreciate the link. Will review it in depth tonight. But pardon my curiosity if the calcium levels are already at acceptable levels, why do we need to dose calcium when we aredosing for alkalinity?

I would. Calcium tests cannot detect changes as readily as alk tests because calcium moves so slowly. If you wait until you think you need it, you’ll be adding many days worth.

That said, if calcium is above 550 ppm, I’d hold off on dosing it. :)

 

[sumpreef]

So I bought the BRS two part along with Tropic marine part C with the trace elements. Along with magnesium for a total of four separate dosage containers.

I dosed the soda ash solution yesterday to increase my DKH by .2. I did it manually drop by drop in an eye flow area and noticed snowflake like precipitate forming right away which I assume is from the high PH local magnesium precipitate that forms based on the other thread.

My pH is already at 8.2. My question is if I mix another gallon of sodium bicarbonate solution and mix this with the gallon of soda ash that I made yesterday for a total of 2 gallons of dkh solution. Will it work to help reduce some of the precipitation from forming.

I will just end up using 1.5 times the amount for the soda ash calculation. Ie use 15ml of this new liquid if the calculator says I need 10ml of soda ash solution

Curious to hear your thoughts

 

[Privateye]

I've seen this happen many times when comparing API to other brands. It tends to be user error.

The problem is usually that the drops added with the API kit are too small, meaning it takes more of them to reach the same volume as compared to larger drops. More drops means you read a higher alkalinity. This can happen from:

1. Bubbles in the drop
2. Adding drops too quickly

So once you shake the bottle, let it settle for about 30 seconds to reduce bubbles. When you add drops do it slowly with the bottle completely inverted. Let the drops "fall" from the tip once they're large enough. This is what one of my former bosses taught me.

When new people at work use the API kit they tend to go quickly, and get very high values. Much higher than they would get with Salifert. However, when I run those two tests they come out the same. This trick should fix it.

Getting down to the theory, these titration kits all work the same. You add an indicator to the sample, then you add an acid until the pH reaches 4.5 (don't quote me on the number) and the indicator triggers. The brand isn't usually the issue - it's how the test is being run.

 

[Peer.Boerner]

Excellent advise. I also think it helps to hold the bottle directly upside down and not at an angle. This ensure very even drop size.

 

[sumpreef]

Thank you very much for the tips on the API test kit. Will try it tonight. Any thoughts about the dosing question with combining baking powder and soda ash?

 

[Randy Holmes-Farley]

So I bought the BRS two part along with Tropic marine part C with the trace elements. Along with magnesium for a total of four separate dosage containers.

I dosed the soda ash solution yesterday to increase my DKH by .2. I did it manually drop by drop in an eye flow area and noticed snowflake like precipitate forming right away which I assume is from the high PH local magnesium precipitate that forms based on the other thread.

My pH is already at 8.2. My question is if I mix another gallon of sodium bicarbonate solution and mix this with the gallon of soda ash that I made yesterday for a total of 2 gallons of dkh solution. Will it work to help reduce some of the precipitation from forming.

I will just end up using 1.5 times the amount for the soda ash calculation. Ie use 15ml of this new liquid if the calculator says I need 10ml of soda ash solution

Curious to hear your thoughts

There’s no real chance the pH gets too high with soda ash.

You can mix and dose them as you suggest, but the transient precipitation of magnesium hydroxide is no concern at all. It redissolves,

 

[sumpreef]

OK, thank you. I saw the snowflake like precipitation form. It was hanging out in the sump for a little bit before getting sucked up by the return pump. I was just worried overtime that this will clog up the impellers in the pump.

 

[Randy Holmes-Farley]

OK, thank you. I saw the snowflake like precipitation form. It was hanging out in the sump for a little bit before getting sucked up by the return pump. I was just worried overtime that this will clog up the impellers in the pump.

Assuming you are dosing to a reasonably high flow area and not right into the return pump inlet, that should not be a concern.

 

[sumpreef]

Yeah dosing right next to the skimmer outflow. So it then goes to the bubble trap and then the return section