PH Issue and Alkalinity

[Mortaliton]

Good Afternoon

I have had freshwater aquariums for close to 15 years now. I have had great success as well. However, I have decided I will now get my first Saltwater Tank and very long term, future reef tank up and going. I have my own RoDi unit and make my own water and I am able to get the salt levels to the correct amount.

However after watching many videos on youtube and much research I am still baffled at my current issue. The main tank is still cycling as of these measurements. 0 Ammonia, and sky high nitrites but that is to be expected. I have read that this can throw off my PH as well but tested it for comparison. It is a 125 gallon tank. I have a separate Food Safe Brute 44 gallon barrel as well to premix my water for water changes. This is my other comparison.



Currently My premixed Reservoir Rodi Water and with Only Salt sits at
- Meq/L - 3
- dKH - 8.4
- PH - 7.6

Currently my 125 Gallon Tank ( Still Cycling ) sits at
- Meq/L - 4.25
- dKH - 11.9
- PH - 7.6


In the main tank I have used Seachem Reef Buffer to boost the PH to 8.3. In the Mixing Reservoir I have used Seachem Kalkwasser to boost the PH to 8.3. However I would say a rough estimate of 10-12 hours later. Overnight basically. The PH would return to 7.6 . I understand Alkalinity is basically a buffer to prevent PH swings. From what I understand that products even like Kalkwasser need to be dosed to maintain depending on the load of the aquarium. I just cannot wrap my head around such a massive drop in what seems to me as a low time frame. Especially in a reservoir with no load. I want to have it even with the tank when I do water changes.

I understand that C02 also plays a role in the PH of water. I have a C02 test kit coming tomorrow to provide some light on my current levels. I do have my protein skimmer off currently while the tank cycles since I dosed with Fritz Saltwater.


Any Insight would be much appreciated.

Thank You In Advance

 

[Greenycrew]

unlike in freshwater tanks adjustment of ph is often unnecessary and is frequently low during the cycling period. I would focus on aeration, water movement and keeping appropriate dkh. Reef tanks are fine with ph values above 7.8. Also how are you checking ph. I would highly recommend an electronic tester

 

[Randy Holmes-Farley]

Low pH (if accurate) at normal or high alk is caused by excess CO2 in the water. Often that is caused by excess CO2 in the home air.

 

[Mortaliton]

I am using a electronic tester for PH and Salt concentration.

Over the last day I did dose kalkwasser to my resivoir and the oh held this time. Looking at an average of dropping .1 a day now. I have not got a change to re test the alkalinity but assuming it’s higher with more kalkwasser.


We’re going into summer time so the windows will be open more. But I’m trying to think of a way to directly pump external air directly through my air pump. Not sure if that’s a thing or possibility without external equipment. Maybe a C02 scrubber would just be the way to go.

 

[Mortaliton]

Apologies for double post. I am on my phone and not PC at the moment. I do not see a edit button at least on IOS.

After a quick google search I realize CO2 sinks in a room. My air pump is almost on the floor. Bottom of aquarium cabinet. I put it on a shelf above my aquarium not enclosed to see if this makes a difference not being on ground level.

I have never had to worry about PH, ever while in freshwater. Maybe live plants, ect, luck. So maybe this is common knowledge but not to me just yet. I got a base PH of 7.65 right now. I’ll test tomorrow and later to see if it changes.

Appreciate the input so far all.

 

[KStatefan]

I am using a electronic tester for PH and Salt concentration.

Over the last day I did dose kalkwasser to my resivoir and the oh held this time. Looking at an average of dropping .1 a day now. I have not got a change to re test the alkalinity but assuming it’s higher with more kalkwasser.


We’re going into summer time so the windows will be open more. But I’m trying to think of a way to directly pump external air directly through my air pump. Not sure if that’s a thing or possibility without external equipment. Maybe a C02 scrubber would just be the way to go.

I would use baking soda to adjust the alk in your reservoir instead of kalk.

I pump air from outside to my skimmer. The pump is inside.

 

[Mortaliton]

I would use baking soda to adjust the alk in your reservoir instead of kalk.

I pump air from outside to my skimmer. The pump is inside.

Just plain old baking soda is safe for saltwater / reef? Assuming no additives just straight baking soda?

My air pump doesn’t have an intake. I was thinking about running 25 ft to the outside and having it in a container with holes even just for testing. If it works then figuring out something long term.

 

[KStatefan]

Just plain old baking soda is safe for saltwater / reef? Assuming no additives just straight baking soda?

My air pump doesn’t have an intake. I was thinking about running 25 ft to the outside and having it in a container with holes even just for testing. If it works then figuring out something long term.

Yes

You can use this calculator to calculate how much is needed. I like to use Randy's recipe #2 to have a solution to add.
297 grams of baking soda to make 1 gallon of solution.

Reef Chemistry Calculator

 

[Mortaliton]

I ordered a roll of tube. I’m going to tube my protein skimmer and air pump to pull only air from outside.

I’m going to have an air tight container. I actually have an old air intake from a pellet stove I don’t use anymore. So that will attach to the side of the container that way it pulls air directly from outside.

I’ll have my air pump inside it so it’s forced to pull the air. I’ll tap another hole as well so the protein skimmer can feed directly from the fresh air to.

My only concern is that each tube will be about 15-16 feet long. I have never ran a tube that long before. Will the resistance be to much? Or one of those things you just have to try to see if it works.

I’m running this air pump. 12 watts and meant for a large tank.

https://a.co/d/beEPWrY

 

[Randy Holmes-Farley]

Apologies for double post. I am on my phone and not PC at the moment. I do not see a edit button at least on IOS.

After a quick google search I realize CO2 sinks in a room. My air pump is almost on the floor. Bottom of aquarium cabinet. I put it on a shelf above my aquarium not enclosed to see if this makes a difference not being on ground level.

I have never had to worry about PH, ever while in freshwater. Maybe live plants, ect, luck. So maybe this is common knowledge but not to me just yet. I got a base PH of 7.65 right now. I’ll test tomorrow and later to see if it changes.

Appreciate the input so far all.

No, CO2 that is mixed into air does not ever settle in a room. Moving an air pump around will make no difference unless there is a localized point source of high CO2 on the floor (like a bucket of dry ice).

An important chemical principle is that gases, once mixed, do not separate and dissolved chemicals in water also do not settle or rise.

There are extreme cases, like in a high speed centrifuge at massive g forces where that is not always true, but that’s not the case here.

 

[Mortaliton]

No, CO2 that is mixed into air does not ever settle in a room. Moving an air pump around will make no difference unless there is a localized point source of high CO2 on the floor (like a bucket of dry ice).

An important chemical principle is that gases, once mixed, do not separate and dissolved chemicals in water also do not settle or rise.

There are extreme cases, like in a high speed centrifuge at massive g forces where that is not always true, but that’s not the case here.

Thank You for the insight. I did not know that so good to know.

The results thus far with that in mind, I attribute to better air flow with the windows finally open, yay summer. I went from 7.6 to 7.77

Now, I was fully able to install my air pump in an enclosed air tight container. With a fresh air intake directly to the outside. 18 foot tube run. Both the air pump and protein skimmer work perfectly still. From what I read about resistance and definitely not a Pro in that area in any means. I attribute to being a 12 watt pump and just strong, I cannot say this would work for weaker pumps. The protein skimmer working off a 18 foot run I attribute to pure luck lol.

I’ll update in a day or so waiting on the results for a different air source for the pump.

Thanks all for the input this far.

 

[Mortaliton]

Alrighty. I know it was more than a couple days but since their tank was still cycling I figured and data would be pointless until cycled.

The tank finished cycling a week ago. Oh is stable at 7.65 to 7.81 throughout the day without bufffers. I have added Kalkwasser and a KH buffer but within 6 hours or so my alkalinity and ph both tank. KH goes down as well.


Now that the cycle is done. The UV light is back on, and the protein skimmer is on as well. The skimmer also pulls fresh air from the outside. I can’t imagine it being a CO2 issue but I’m new so maybe I’m wrong. Oh drops on average from 8.3 to 8 writhing 3 hours, .1 a hour. Alkalinity follows suit.

At this point I have settled in to the fact is it’s a new tank and need to just let it play out. After talking to a LFS, open since 1975. They had captive bred clowns. They said the ph I have without buffers is good for them.

So I got 2 clowns and they are doing good for 2 days now. Eating swimming, just being clowns with no abnormal behavior.

I am going to run for 2 weeks or and see if I can’t slowly creep the alkalinity up but something is still eating it up at a expedited pace.

My saltwater Reservoir goes down in ph but it’s .1 a day. Not an hour. So either nothing in my tank is eating alkalinity or it’s just because it’s new.

I do have brook rocks in the tank, however I did test every rock before putting them in back when it was freshwater. And none of them reacted.

This is all I got for now but unless anyone has and leads to follow. I’ll update in 2 weeks or so when the tank has aged more.

Cheers!

 

[azreefer93]

Alrighty. I know it was more than a couple days but since their tank was still cycling I figured and data would be pointless until cycled.

The tank finished cycling a week ago. Oh is stable at 7.65 to 7.81 throughout the day without bufffers. I have added Kalkwasser and a KH buffer but within 6 hours or so my alkalinity and ph both tank. KH goes down as well.


Now that the cycle is done. The UV light is back on, and the protein skimmer is on as well. The skimmer also pulls fresh air from the outside. I can’t imagine it being a CO2 issue but I’m new so maybe I’m wrong. Oh drops on average from 8.3 to 8 writhing 3 hours, .1 a hour. Alkalinity follows suit.

At this point I have settled in to the fact is it’s a new tank and need to just let it play out. After talking to a LFS, open since 1975. They had captive bred clowns. They said the ph I have without buffers is good for them.

So I got 2 clowns and they are doing good for 2 days now. Eating swimming, just being clowns with no abnormal behavior.

I am going to run for 2 weeks or and see if I can’t slowly creep the alkalinity up but something is still eating it up at a expedited pace.

My saltwater Reservoir goes down in ph but it’s .1 a day. Not an hour. So either nothing in my tank is eating alkalinity or it’s just because it’s new.

I do have brook rocks in the tank, however I did test every rock before putting them in back when it was freshwater. And none of them reacted.

This is all I got for now but unless anyone has and leads to follow. I’ll update in 2 weeks or so when the tank has aged more.

Cheers!

I got this PH issue over the last few months when I start my new tank as well. What I have learn so far is the cycling process (which bacteria breakdown the organics) is creating CO2 which lower your PH as well. So you are right on the first point which the PH number is pointless before the tank is cycled. I think PH issue is absolutely CO2 issue. But glad you got the PH increase to 8-8.3. I'm still struggling around 7.8-8.0 (APEX) - my tank 120 gallons, dosing 2400ml Kalk daily, 25ml AFR, running airstone to the sump and skimmer take outdoor air. Before I do all of this, my PH was 7.6. One more thing that I am observed is high ALK consumption when higher PH.

 

[Mortaliton]

I got this PH issue over the last few months when I start my new tank as well. What I have learn so far is the cycling process (which bacteria breakdown the organics) is creating CO2 which lower your PH as well. So you are right on the first point which the PH number is pointless before the tank is cycled. I think PH issue is absolutely CO2 issue. But glad you got the PH increase to 8-8.3. I'm still struggling around 7.8-8.0 (APEX) - my tank 120 gallons, dosing 2400ml Kalk daily, 25ml AFR, running airstone to the sump and skimmer take outdoor air. Before I do all of this, my PH was 7.6. One more thing that I am observed is high ALK consumption when higher PH.

I’m sitting at 7.65-7.8 without buffers or Kalk.

I actually used an old pellet stove air intake and converted it into an air pump box. So all my air for my air pump and protein skimmer is taken from outside. That why I’m boggled now on why it won’t go up it related to CO2. That said I’m pretty sure it isn’t CO2 at this point vs maybe although on the surface it looks like the cycling is done but maybe the bacteria are still reproducing so close to end of cycle eating away at my alkalinity. Maybe producing CO2 as well of reproducing even if my chemicals are all 0.

 

[Mortaliton]

Final Update

Hopefully this helps any other newcomers with my experience. Although I have had fish for over a month. The PH would remain low. I am currently just getting out of the diatom phase of mass growth. I still get some on the glass but it’s no longer covering the sand.

I do have gobies now, so that probably helped to some extent. I have also added a refugium with Chaeto.

Again all air is pulled from outside. About 10 days ago my PH shot up to 8.27 and has maintained constantly throughout the day.

So my end feedback from this, is although the tank was cycled and could easily house more hardy fish. It took about 2-3 months in total to fully establish itself from the start of the cycle. Honestly probably has more to go. Just the ph swings go back to new tank. Unfortunately I found there was only one solution and that is patience. So anyone who is new like me wondering why they can’t maintain it.

I hope this helps. Thank You to the community who helped me diagnose.

Cheers