Kalk vs Baking Soda for pH

[Rovert]

I've been struggling to keep my pH much above 7.4-7.5 even during daytime hours with the lights on, and running my skimmer 24/7. I'm trying to determine if I need to dose Kalk, Baking Soda or both to get where I need to be. Tank volume is about 200 gallons total volume. Could use some help.

Thanks!

 

[Uncle99]

That’s very low, have you double checked the result. Is it in a very confined area with little air exchange?
If your confident, Id use Kalk as we get both Alk and PH.

 

[Rovert]

Yeah, pretty sure. I'm running a Seneye monitor, they're reported to be pretty accurate. Windows open in the room, ceiling fan running, skimmer going 24x7, I just can't seem to get much above 7.5 no matter what. I just mixed up some Seachem Kalk, and added it by way of the skimmer feed pump. Let's see what happens next.

Thanks!

 

[Reefing102]

Do you do water changes? Maybe consider testing freshly mixed saltwater to see what your baseline may be

 

[kharmaguru]

Yeah, pretty sure. I'm running a Seneye monitor, they're reported to be pretty accurate. Windows open in the room, ceiling fan running, skimmer going 24x7, I just can't seem to get much above 7.5 no matter what. I just mixed up some Seachem Kalk, and added it by way of the skimmer feed pump. Let's see what happens next.

Thanks!

I found my seneye always read low on PH. I used to test with salifert and then trim the seneye to match. It stayed accurate after trimming.

I wouldn't dump in Alk additives willy nilly. Could precipitate and make the situation worse. Just use them to adjust ALK not PH. Windows wide open is a good idea. Running the skimmer air line outside is helpful. Could also add a CO2 scrubber to the skimmer line but I consider that costly long term.

 

[Vinny Kreyling]

Robert, what does new water test to?
PH generally has a mind of its own.

 

[Rovert]

Robert, what does new water test to?
PH generally has a mind of its own.

Assuming pH is the same between fresh and salt water, I'm showing 7.4 from the ro/di. Having a lot of difficulty maintaining a higher level. Last night with the lights on and dosing Kalk periodically through the day I hit 7.56 late last night, this morning I'm back to 7.43 at best. I won't rule out that the 'slide' in the Seneye is bad, but that's a stretch. Wondering if I should mix Kalk and baking soda...

 

[Vinny Kreyling]

The salt mix should raise PH after mixing.
They do say the kits will read both fresh & salt.
Mix the kalk into your make up water.
Years back Greg Schimer said all make up water should have kalk in it.

 

[Rovert]

Mix the kalk into your make up water.

Not practical for me. My tank has an ATO reservoir built into the back. The kalk will settle out and I have no way to stir it up. So I'm back to wondering which is better, if I should mix Kalk and Baking Soda. Is one more effective than the other?

 

[kharmaguru]

Not practical for me. My tank has an ATO reservoir built into the back. The kalk will settle out and I have no way to stir it up. So I'm back to wondering which is better, if I should mix Kalk and Baking Soda. Is one more effective than the other?

Kalk and baked baking soda/soda ash (sodium carbonate) raise PH. Baking Soda (sodium bicarbonate) initially lowers PH but will rebound in a few hours.

PH is 100% dictated by the concentration of CO2 in your water. CO2 from resperation and photosynthesis of aquarium inhabitants + CO2 in the home's air from humans and pets. You could run your ALK at 12 dkh and still have low PH. The best course of action is to target a set alkalinity value with the above additive of your choice and then figure ways to mitigate CO2. Reverse schedule refugium, run external skimmer air line, CO2 scrubber, etc. Trying to chase PH with kalk will just lead to your pumps and heaters covered in calcium deposits from precipitation.

 

[Rovert]

I have a fairly large home with only myself and a cat, the room windows are open and I'm running a ceiling fan for the majority of daytime hours, so I don't think the room CO2 is the problem. The skimmer draws on room air, but I suppose I can work on getting the sump illuminated so my macro grows better and pulls out the C02 better. I also have to work on better in-tank circulation, that will probably help also.

Wondering if firing up my calcium reactor and piping the effluent through the skimmer might be the way to go. Any thoughts?

Thanks for the ideas!

 

[kharmaguru]

I have a fairly large home with only myself and a cat, the room windows are open and I'm running a ceiling fan for the majority of daytime hours, so I don't think the room CO2 is the problem. The skimmer draws on room air, but I suppose I can work on getting the sump illuminated so my macro grows better and pulls out the C02 better. I also have to work on better in-tank circulation, that will probably help also.

Wondering if firing up my calcium reactor and piping the effluent through the skimmer might be the way to go. Any thoughts?

Thanks for the ideas!

No problem. I'm not sure why you trust the seneye ph reading so much when there are literally a 100 threads in a google search where it reads wrong for people ( high or low) and requires trimming. Considering everything you are doing should not produce an excessively low PH, I would verify the reading against another reliable test (if you've done that - apologies). Chasing PH is a nightmare on the best of days.

 

[Rovert]

I'm not sure why you trust the seneye ph reading so much when there are literally a 100 threads in a google search where it reads wrong for people ( high or low) and requires trimming.

Haven't researched those threads, but per above, I did allow for the idea that the Seneye might be wonky. I'll grab a backup test kit just to have a confirmation. So far all the tank critters seem to be OK, so a bad reading could easily be the answer.