Aquarium Chemistry Question? Ask the Doctor!

[Randy Holmes-Farley]

Dear Dr. Randy,

When we talk about alkalinity in a reef tank, is it Alkalinity (M), Alkalinity (P) or Alkalinity (Total)?

Best,
Rabih

Total alkalinity.

I discuss it here:

Chemistry and the Aquarium: What is Alkalinity? ? Advanced Aquarist | Aquarist Magazine and Blog
http://www.advancedaquarist.com/2002/2/chemistry

 

[Randy Holmes-Farley]

I have a question. Why does my ph rise to 8.47 during lights on and then It drops to 7.98 at night until my lights go back on. I'm using xr15pro with ramp up and ramp down. My peak is from 2pm to 5pm.

That is normal. Photosynthesis consumes CO2 during the day, raising pH.
Respiration is constantly adding CO2, and at night it predominates, reducing pH.

 

[revhtree]

Thanks Randy for taking care of our sick tanks! HA!

 

[drernesto]

Thanks Randy for taking care of our sick tanks! HA!

He should take care of our sick addiction to our tanks too [emoji3]

 

[Randy Holmes-Farley]

That's a lot harder. lol

 

[Randy Holmes-Farley]

That's a lot harder. lol

 

[JadeM]

how do you raise your ph using bicarb soda? thanks

 

[Randy Holmes-Farley]

how do you raise your ph using bicarb soda? thanks

You don't. It will reduce pH slightly, and will boost alkalinity.

I address pH issues and how to correct them here:

pH and the Reef Aquarium - REEFEDITION
http://www.reefedition.com/ph-and-the-reef-aquarium/

 

[andys]

Hi

Is it possible to test the strength of freshly made alk solution

 

[Randy Holmes-Farley]

Hi

Is it possible to test the strength of freshly made alk solution

Yes, but it is very high and will need dilution. What did you make?

 

[andys]

Yes, but it is very high and will need dilution. What did you make?

well my issue is i used a half cup measuring cup and i think i may have put 5 half cups in when it only calls for 4. sorry does that make sense

 

[RadagastWizard]

Hello Mr. Farley I have a question regarding going to college for biology, more specifically fisheries or biotechnology and I'm wondering what the outlook is and if you have any advice.

Also, can you get a job outside of the area you went to college?

Thanks,
Luke

 

[Randy Holmes-Farley]

Hello Mr. Farley I have a question regarding going to college for biology, more specifically fisheries or biotechnology and I'm wondering what the outlook is and if you have any advice.

Also, can you get a job outside of the area you went to college?

Thanks,
Luke

Sorry, I'm not really familiar with the job prospects in that area. Most of my professional experience is in pharmaceutical discovery.

 

[Baker91]

Hi randy. I'm needing help with some mag. I have mag crystals but I don't understand your diy. And the brs calculator isn't helpful either. can I use just magnesium chloride or do I need something else?

 

[Randy Holmes-Farley]

What else are you dosing?

 

[Baker91]

Sorry I took so long to reply I'm dosing calcium and need to dose mag. I made your two part do I need to use the bra calculator to figure out my dose? I also got my daily dosing chart form one of your articles. Just need help with the first dose to raise it up to my target level

 

[Randy Holmes-Farley]

You can use this calculator:

http://reef.diesyst.com/chemcalc/chem_calc3.html

 

[mps026]

Hi randy, for the longest time my tank needed the same amount of calcium and alk. I recently changed my light and it seems everything has been thrown off with me having to cut back dramatically on dosing both. Is this normal as the corals adjust to a new light?

 

[Randy Holmes-Farley]

Lighting changes can take some time to adjust to. Light can also be too bright for some corals.

 

[chomoney]

My dumb question:

If I am running an air pump/air stone in a room with high C02 levels, is the air stone simply pumping the C02 laden air into the tank? Or does the air pump/stone still somehow displace C02 within the tank?

My assumption is that it is putting C02 laden air into the water since the air pump has no method of scrubbing the C02, but hoping someone more knowledgeable than me can confirm.

Thanks!