Steadily dropping alk and ph no corals

[rueric]

I set up a transfer tank as I restart my dt.
Tank has completely cycled for about a month now
Cycled with biospira and ammonia from dr Tim’s.

My alk and ph drops fairly rapidly after a water change.. trying to supplement with big water changes to keep it maintained.

Planning to do another 20-30% change after a 30% yesterday.

I have no substrate, only dry rock, HOB filter with a clay pot and some pvc

Live stock I have a cleaner shrimp, two clowns, and a tuxedo urchin.

Is this normal as my tank stabilizes with time?

 

[BanjoBandito]

What salt do you use? I had issues with Red Sea coral pro salt starting with high alk and it would just disappear day over day. Sometimes more than 1 dkh a day. I use alkalin8.3 as a straight ALK dose and even that still didn’t keep it up, it helped but it didn’t. So I actually switched salt and now I’m losing .2-.3 a day which is acceptable to me with corals involved.

also, early on in another tank I had a glass lid on my tank and I learned some stuffs and figured out the relationship with CO2 and alk/ph problems. I removed the lid, added a bubbler and it fixed it over night.

 

[rueric]

I was using IO regular as part of the cycling. I am now switching over to Red Sea blue bucket.
I did my first water change (30%) with blue bucket just yesterday.

I took a reading of my alk and phosphate yesterday (pre-water change)
my alk was reading 4.92! (I didn't believe it at first but I did a second test (Hanna checker) and it was reading the same.
my phosphate at the time was reading 0.09

I have a reef-pi pH sensor (not calibrated yet, waiting on the calibration solution).
The reef-pi pH sensor was installed last night (post-water change) and started the reading at 7.57
I've seen a steady decline of pH and at the time of this writing, it is reading 7.44
Also for the pH sensor, I've tested my recent batch of freshly mixed red sea salt water to see how off the calibration can be.
It read the freshly mixed water at 8.1 (Red sea batch results state my salt mix should be 8.39).
This leads me to believe that, even though my pH sensor has not yet been calibrated, it can't be THAT far off.

What I'm wondering is, are these consistently declining levels due to my tank being "new"?
Or is something I'm doing wrong in terms of husbandry..
I feed nori which might be lodged somewhere around the tank.. or maybe something else?
Could by urchin be causing this? Or maybe a pending algae bloom?

 

[KrisReef]

I believe that dry rock can absorb alk. Maybe start dosing to help speed up the process?

 

[BanjoBandito]

PH is HEAVILY influenced by CO2. PH is basically how many free hydrogen atoms you have floating around. If PH is low, then the hydrogen bonds with your carbonates and sucks you alk, converting it into something else....I think that’s right, my notes are not near by. If you are chasing PH I wouldn’t. I would focus on the ALK, the PH will settle if ALK is stable.

 

[BanjoBandito]

There’s also a relationship between ALK, Ca and Mg....you can’t jack up calcium without a negative impact on the ALK and vice versa. What’s your general tests for Ca and Mg? Is something going on there or are they “fine”???

 

[rueric]

should i try dosing baking soda? i haven't started dosing yet as I'm still setting that up.. Waiting for the all for reef powder to come into US but what should I dose in the mean time?

I am not checking for Ca or Mg at the moment, let me go and run my full gamut of tests..
I have the Hanna Calcium/Alk/Phosphate ULR test kits..

I have the API reef test kits as well but some are expired and typically frowned upon for use

 

[Brian_68]

Check the CO2 levels in your house, this can drop ph considerably, and alk.

 

[rueric]

I’ll have to get a co2 meter.. don’t have one on hand. It’ll be here Wednesday

 

[rueric]

Finished my testing.. even with these Hanna checkers, they aren’t as fast to do!


5/23

Calc 466

Alk 101 (5.46dkh)

Po4 0.9

 

[Reef.]

I had the same happen, many things use alk apart from corals, even nitrates will affect your alk, I dosed baking soda until the alk drop stabilised then moved on to All for Reef once I was at the level I wanted to keep my tank.

 

[rueric]

I had the same happen, many things use alk apart from corals, even nitrates will affect your alk, I dosed baking soda until the alk drop stabilised then moved on to All for Reef once I was at the level I wanted to keep my tank.

Thanks! Just did another water change.. going to clean up and start doing some research on baking soda

 

[BanjoBandito]

Thanks! Just did another water change.. going to clean up and start doing some research on baking soda

You should "bake" it, it won't drop your PH if you bake it....it'll actually raise your PH too.

 

[arking_mark]

A couple thoughts here:
1.pH is probably dropping due to higher indoor CO2 levels. However, I would question a pH reading below 7.8 or you may need to better aerate your water.
2. You're alk reading is also very suspect unless something is consuming it. Generally speaking Alk/Ca is consumed at the same rate. Unless you dosed something to raise Ca, or had very high Ca/Alk, you're numbers just aren't right.
3. I just recommend larger water changes with a quality salt over the next several weeks.

 

[Deep]

I was using IO regular as part of the cycling. I am now switching over to Red Sea blue bucket.
I did my first water change (30%) with blue bucket just yesterday.

I took a reading of my alk and phosphate yesterday (pre-water change)
my alk was reading 4.92! (I didn't believe it at first but I did a second test (Hanna checker) and it was reading the same.
my phosphate at the time was reading 0.09

I have a reef-pi pH sensor (not calibrated yet, waiting on the calibration solution).
The reef-pi pH sensor was installed last night (post-water change) and started the reading at 7.57
I've seen a steady decline of pH and at the time of this writing, it is reading 7.44
Also for the pH sensor, I've tested my recent batch of freshly mixed red sea salt water to see how off the calibration can be.
It read the freshly mixed water at 8.1 (Red sea batch results state my salt mix should be 8.39).
This leads me to believe that, even though my pH sensor has not yet been calibrated, it can't be THAT far off.

What I'm wondering is, are these consistently declining levels due to my tank being "new"?
Or is something I'm doing wrong in terms of husbandry..
I feed nori which might be lodged somewhere around the tank.. or maybe something else?
Could by urchin be causing this? Or maybe a pending algae bloom?

The important question is what is the Alk in your freshly mixed salt water ?

 

[rueric]

Alk is at 8.26 for a freshly mixed salt.

So.. I opened up the windows and left it open for a few hours now and I am seeing my pH steadily rise.
The turning point is the time I opened up my windows.
This is turning out to be likely a build up of Co2 as the cause..
I am going to leave the windows up for the time being until it plateaus..
Wondering if I should continue with another water change to bring my alk back up to see if that holds steady as well?
I haven't done another alk test since my water change last night (30%)

 

[arking_mark]

Alk is at 8.26 for a freshly mixed salt.

So.. I opened up the windows and left it open for a few hours now and I am seeing my pH steadily rise.
The turning point is the time I opened up my windows.
This is turning out to be likely a build up of Co2 as the cause..
I am going to leave the windows up for the time being until it plateaus..
Wondering if I should continue with another water change to bring my alk back up to see if that holds steady as well?
I haven't done another alk test since my water change last night (30%)

Your pH # is still suspect below 7.8. I don't believe your meter is correctly measuring this unless your tank doesn't have enough aeration.

You can do a simple cup aeration test to help identify the issue.

A 7.6pH with 8.29 Alk, would put your pCO2 level around 2400. Indoor air is usually under 1000.

 

[rueric]

No, sorry for the misunderstanding.
My freshly mixed salt water has an alk of 8.29 with a pH of 8.13

I don't know my current Alk in the tank as I haven't measured it since last night before my water change

 

[rueric]

Your pH # is still suspect below 7.8. I don't believe your meter is correctly measuring this unless your tank doesn't have enough aeration.

You can do a simple cup aeration test to help identify the issue.

A 7.6pH with 8.29 Alk, would put your pCO2 level around 2400. Indoor air is usually under 1000.

What is a cup aeration test?

 

[Reef.]

A water change is not the best to bring your alk up, as it would have to be a very big change to work, better using baking soda, if you bake it in the oven for an hour you'll see a slight ph raise too, unbaked it'll drop your ph slightly for a little while.

I would first make sure your water surface is being broken with your powerheads or return, and the room is well aired, then wait to see when the ph stabilises what that does to the alk, then maybe add the baking soda but no more than a .5kh raise a day is probably best.