Low ph dissolve corals

[bubbaque]

Randy I read somewhere where you wrote corals start to dissolve at a ph of 7.7. How do people with tank ph slightly lower than that keep and grow corals?

 

[nautical_nathaniel]

I don't think I've heard of any successful reefs with a pH that low. Do you have an example of one?

 

[bubbaque]

One of the best tanks I have seen is reefnjunkie. His ph runs 7.65 to 7.9. Mine also runs 7.65 to 7.85 and I seem to grow coral fine.

 

[nautical_nathaniel]

One of the best tanks I have seen is reefnjunkie. His ph runs 7.65 to 7.9. Mine also runs 7.65 to 7.85 and I seem to grow coral fine.

Well in that case, corals don't melt below 7.7 it wouldn't surprise me though if they started getting pretty upset if it got much lower.

 

[bubbaque]

I’m wondering what’s stopping it from happening. I am trying to grasp the chemistry.

Are my corals actually dissolving and then rebuilding during the day when the ph is slightly higher? I don’t have burnt tips.

 

[TUSI]

I always thought that ph at lower than 7 will melt coral. 7 is neutral. If My understanding is correct

 

[nautical_nathaniel]

I’m wondering what’s stopping it from happening. I am trying to grasp the chemistry.

Well in order for the coral's skeleton to dissolve, it would need to be subjected to acidic conditions which will happen after the pH drops below 7.

 

[Abhishek]

Well @bubbaque - I wont say my reef is successful yet as its less than a year old but my pH runs always low and even sometimes 7.6.

90% acro tank and even has some of the most finicky acros in the trade like OG Purple monster, BC Angelica , BC Gilligan and Oregon Tort .
All my acros are alive and encrusting fine and as far as I can see them right now, nothing has melted

I have tried several things but realised chasing pH caused more instability in tank .
Hence I resorted to low pH . Its better to have low stable pH than highs and lows I believe . Now I run 7.7-7.9.

And yes I have calibrated my pH probe every 3- 4 months .

Regards,
Abhishek

 

[bubbaque]

I understand a stable ph is WAY more important than a high one. I don't feel my corals are melting either and I posted some pics of my sps and they seem to be encrusting and growing. I am wondering why that is the case if they are suppose to be melting once my ph goes below 7.7. Since my tank isn't in the 7.65 range long as my lights start turning on and it reverses, maybe it's not in the range long enough to cause noticable damage.

@Abhishek your tank now I see running just above or at the range where thing should start to melt. So I'm not sure you would see the negative of it or if there even is a negative of it. Ne t time it dips to 7.6 see if you notice anything different, such as thinner sps skin.

@nautical_nathaniel i know for sure that calcium media starts to dissolve at a least a ph of 7.4. I set up my calcrx from a video where you have a high flow rate and start at a high ph.

 

[bubbaque]

Well in order for the coral's skeleton to dissolve, it would need to be subjected to acidic conditions which will happen after the pH drops below 7.

7 or 7.7?

 

[TUSI]

7 or 7.7?

7

 

[Huskymaniac]

My old tank used to run at 7.7 to 7.9 because of my cal reactor. Never had any issues but since I moved the tank into the basement I am using two part as I am sure oxygen levels are lower down there and i was concerned about the PH dropping further. Calcium reactor starts melting around 7.4 so I woukd be domewhat concerned if I hit the 7.6 range.

 

[bubbaque]

My old tank used to run at 7.7 to 7.9 because of my cal reactor. Never had any issues but since I moved the tank into the basement I am using two part as I am sure oxygen levels are lower down there and i was concerned about the PH dropping further. Calcium reactor starts melting around 7.4 so I woukd be domewhat concerned if I hit the 7.6 range.

I don't think the 7.7 would be an issue. I'm wondering how are people running successful tanks once they hit that 7.69 mark.

I'm more curious how you have a video or live feed automatically start playing in your repl!?! Lol....ah it's a gif, you fooled me. Didn't notice the fish swim backward at first.loL

 

[Huskymaniac]

Haha. One of those live photos on the galaxy.

 

[Abhishek]

I don't think the 7.7 would be an issue. I'm wondering how are people running successful tanks once they hit that 7.69 mark.

I'm more curious how you have a video or live feed automatically start playing in your repl!?! Lol....ah it's a gif, you fooled me. Didn't notice the fish swim backward at first.loL

Honestly I find it very very hard to believe. I have had a month or so when my pH went as low as 7.6 everyday at night due to vacation time and more people in house with no window to open in winter if you live in Coldest state .

Adam from Battlecorals is one who runs system with low pH. Even Jason Fox has it complete system in the basement and if you see his presentation Reef Current 2017, he talks about how he threw away his pH probes and doesnt measure it. With huge calcium reactors and no refugium or kalkwasser and couple that with thousands of gallons in the basement , I wont be surprised if his pH is also low if not lower than most .

Regards,
Abhishek

 

[Huskymaniac]

I would think if you really want to know just set a calcium reactor at 7.5 and measure the effluent comming out. If you see a higher alk comming out than what is in the tank than something is melting. I only measure ph to make sure there arent an swings but there has to be a breaking point of what is not safe. Personally I like to leave some room for error.

 

[bubbaque]

Honestly I find it very very hard to believe. I have had a month or so when my pH went as low as 7.6 everyday at night due to vacation time and more people in house with no window to open in winter if you live in Coldest state .

Adam from Battlecorals is one who runs system with low pH. Even Jason Fox has it complete system in the basement and if you see his presentation Reef Current 2017, he talks about how he threw away his pH probes and doesnt measure it. With huge calcium reactors and no refugium or kalkwasser and couple that with thousands of gallons in the basement , I wont be surprised if his pH is also low if not lower than most .

Regards,
Abhishek

Adams graphs that he showed doesn't look to go below 7.7 once he calibrated it though.
I remember watching JF presentation and listen to him say his ph was low and wishing he actually said what his ph value was but he never did.

If chemistry says they should be melting at 7.69. Why aren't they?

 

[billwill]

My calcium reactor controller is set at 7, so I’m very confident that 7 dissolves calcium carbonate quite nicely. My tank is 7.7-7.9, and seems just fine. Don’t actually ever measure it since alkalinity is the important part of that equation in my mind

 

[Randy Holmes-Farley Verified Community Expert]

Randy I read somewhere where you wrote corals start to dissolve at a ph of 7.7. How do people with tank ph slightly lower than that keep and grow corals?

The dissolution is slow in the mid 7's and goes faster and faster as the pH drops more and more. Corals also cover a lot of their skeletons with tissue which probably helps protect it, so the most dissolution will begin as exposed places, which in many corals are dead areas at the base, in some frag/plug SPS there may be no exposed skeleton once the skeleton down tot he plug is covered.

 

[Randy Holmes-Farley Verified Community Expert]

I always thought that ph at lower than 7 will melt coral. 7 is neutral. If My understanding is correct

Calcium carbonate (aragonite) is only slightly supersaturated at pH 8.2 in normal seawater. You do not have to drop all the way to pH 7 for aragonite to be undersaturated, meaning more can dissolve into the water.