Killed a hammer by dosing Alk the wrong way...

[danbecerra]

Hi, sharing some learning, looking back I guess I did not do my homework to really think how to dose correctly...

So here is the story... I had an unstable tank as my couple LPS (2 hammers, one with 2 heads, another with 4 heads), coraline algae and couple SPS ( montipora and leptoseris small frags) were starting to demand Alk and calcium ,and magnesium, and I was dosing irregularly every 2/3 days manually, then I decided I needed automated dosing, so acquired a dosing pump.

I started a daily measurement to get daily consumption and got 0.5 dKH per day, programmed pump to start on a 6ml dose of DIY baked soda bicarbonate solution, along with calcium chloride solution, after a few days of measuring I saw I was going down by 0.25 dKH so I doubled dosing, now it was 12ml...
After a few days I was still going down by 0.1dKH and increased dosing to 15ml...
It looked fine for some days and then I was going down by 0.15 dKH
At this point I started to get confused, is my tank increasing consumption? I raised dosing to 18ml...
Then I failed to measure daily... Few days later a hammer head had melted, realized this after returning home from work, got a little into panic and did a water change late at night of about 20% sucking up the dissolved coral and surrounding areas trying to avoid Brown Jelly Disease propagation... Couple days later other hammers looked unhappy and I measured parameters, dKH was down to 6.5 , I could not understand why, I had increased dosing ...

After checking carefully dosing pump, I realized it stopped dosing, not because the pump failed, no , pump was working fine, but because the hose tube was completely blocked by calcium carbonate inside, missed to catch this because the hose was not transparent, it was opaque, and the BIG mistake I had made was to let a portion of this dosing hose tube submerged in the sump, It didn't cross my mind previously that I should not let it get submerged , that the alk solution should drop into the sump .. I don't recall seeing instructions about this, but again I did not do my homework, was more focused on other stuff like calculating and calibrating ...

I've reset my measurements and trying to figure out correct consumption, my initial 18ml dosing is now slowly raising Alk being dosed the right way ( dripping, hose not submerged) but that is ok until I get back up to around 8.5 dKH target, then will reduce dosing and see where I end up...

Hammer corals still look unhappy but I guess it'll take some time with stability to recover...

Will update later with some tank pictures and final dosing....

 

[Randy Holmes-Farley Verified Community Expert]

Sorry to hear about this.

Yes, it’s best to not have dosing tubes in the water. Especially not the alk part when using high pH alk sources.

 

[danbecerra]

A few pics of sump with dosing pump and the SPS and LPS on the tank

 

[Sophie"s mom]

WOW! This never occured to me either. I do however, luckily have mine out of the water, But I honestly never thought of this. I just have them out so I can see it when it doses, and I do know that the ALK tube will sometimes get build up at the tip.

 

[jkobel]

I started a daily measurement to get daily consumption and got 0.5 dKH per day, programmed pump to start on a 6ml dose of DIY baked soda bicarbonate solution, along with calcium chloride solution, after a few days of measuring I saw I was going down by 0.25 dKH so I doubled dosing, now it was 12ml...
After a few days I was still going down by 0.1dKH and increased dosing to 15ml...
It looked fine for some days and then I was going down by 0.15 dKH
At this point I started to get confused, is my tank increasing consumption? I raised dosing to 18ml...

Sorry for your troubles. This is a topic that after 20 years I am astonished to admit I still have not been able to lock in on.

I thought this was going in a different direction which is why I keyed in here - Did you end up finding the right dose?

My issue has always been that I have an established mixed tank that I dose ALK with BRS 1.1 about 30ml/day. My ALK has ALWAYS dropped over the course of a week with dosing and I need to make a corrective addition. This has been constant.

I have played with increasing the amount of time I dose and nothing seems to change. Then I get to a point where it seems that the amount im dosing is ridiculous and still making corrections and I drop it back down and things don't really change.

The same story with Ca.

In fact, I just had to remove about 200 square inches of plating Monti because it was covered by BTA and I expected my existing dosing reginmin to send things off the charts and there was a slight spike but the levels continue to drop and im back to making large corrective additions of Ca and ALK. I figured things would stabilize after removing the fastest growing SPS in the tank but they didnt.

Maybe someone that understands this explain what im doing wrong so I can finally get this fixed?

 

[Randy Holmes-Farley Verified Community Expert]

Sorry for your troubles. This is a topic that after 20 years I am astonished to admit I still have not been able to lock in on.

I thought this was going in a different direction which is why I keyed in here - Did you end up finding the right dose?

My issue has always been that I have an established mixed tank that I dose ALK with BRS 1.1 about 30ml/day. My ALK has ALWAYS dropped over the course of a week with dosing and I need to make a corrective addition. This has been constant.

I have played with increasing the amount of time I dose and nothing seems to change. Then I get to a point where it seems that the amount im dosing is ridiculous and still making corrections and I drop it back down and things don't really change.

The same story with Ca.

In fact, I just had to remove about 200 square inches of plating Monti because it was covered by BTA and I expected my existing dosing reginmin to send things off the charts and there was a slight spike but the levels continue to drop and im back to making large corrective additions of Ca and ALK. I figured things would stabilize after removing the fastest growing SPS in the tank but they didnt.

Maybe someone that understands this explain what im doing wrong so I can finally get this fixed?

Can you clarify what product you are dosing and in what amounts when it gets “ridiculous”?

 

[jkobel]

Can you clarify what product you are dosing and in what amounts when it gets “ridiculous”?

BRS 2 part mixed per instructions.

I have had the dose be up to 60 mins or 114 ml and not seen a change. So, in this sense "ridiculous" refers to the amount i'm dosing vs what the result is.

I actually don't know if that dosage is high or not since it didnt make a change for me.

 

[chelltom]

maybe magnesium or calcium too high . This can effect alk I believe ??? Just a thought

 

[jkobel]

maybe magnesium or calcium too high . This can effect alk I believe ??? Just a thought

I've heard that and I'm sure there is truth to it.

CA - 364 - trident
MG - 1168 - trident

I periodically check trident against Hannah and it's consistent.

Calcium has the same issue as ALK where no matter how much I dose it is always being depleted at a higher rate to where I will need to raise CA by 40-50 ppm per week with a corrective dose.

I dose ALK at midnight and CA at 9am to avoid precipitation issues.

 

[chelltom]

I am no expert but those #s seem on the low side for sure

 

[Randy Holmes-Farley Verified Community Expert]

So let’s back up. I expect the magnesium test is in error unless the salinity is very low. Mag tests are a problem and I recommend not testing it at the momment (maybe not at all).

What is the salinity and how are you measuring it?

What is the total system volume?

 

[chelltom]

I think the problem is with your mag its too low

 

[chelltom]

I defer to Randy he is the expert !!

 

[jkobel]

I am no expert but those #s seem on the low side for sure

Yes -
CA is low because I have not corrected in a few days.

Mag is currently low

So let’s back up. I expect the magnesium test is in error unless the salinity is very low. Mag tests are a problem and I recommend not testing it at the momment (maybe not at all).

What is the salinity and how are you measuring it?

What is the total system volume?

The measurements above are from my Trident today.

Here are the results from an ICP test I received yesterday which are below.
Salinity is 1.0216
MG - 1,177
CA - time sample was taken - 308
Alkalinity - 9.1

For reference (and astoundingly) the readings from the Trident at the time I took that sample for the ICP test were this:
Alk - 9.07
CA - 308
MG - 1182
Salinity was a little off at 35.65 (thru apex - no hydrometer reading this day)

typically I track the Salinity with a conductivity probe thru apex. I also cross check with a glass hydrometer when I mix NSW.

total system volume is about 140 gals.

 

[jkobel]

I am no expert but those #s seem on the low side for sure

I completely agree the numbers are low, which is what this is all about.

I am not able to keep my numbers high enough even with automated dosing - im looking for help on how to correct my dosing process because something is not working.

 

[jkobel]

recent IPC results if this help - https://lab.faunamarin.de/en/share/analysis/238035

 

[Randy Holmes-Farley Verified Community Expert]

The salinity is very low, which is why calcium and magnesium are low, if sg = 1.0216 is correct.

 

[jkobel]

The salinity is very low, which is why calcium and magnesium are low, if sg = 1.0216 is correct.

Just checked the tank with my glass hydrometer which is reading 1.0263 at 78.4 degrees

im surprised that the ICP test that far off TBH

 

[Randy Holmes-Farley Verified Community Expert]

Just checked the tank with my glass hydrometer which is reading 1.0263 at 78.4 degrees

im surprised that the ICP test that far off TBH

FWIW, I thought that value was specific gravity. Fauna Marin says it is density, which is different. It’s still low by their measurement, but not as low as I thought.

 

[jkobel]

FWIW, I thought that value was specific gravity. Fauna Marin says it is density, which is different. It’s still low by their measurement, but not as low as I thought.

Going back to the original question - how do we find the right dose when increasing the dose daily doesn't seem to make a difference?