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JCOLE
Grower of the Small Polyps
I haven't performed the tests yet. We got another winter storm and I am waiting for that to clear up before going outside. Will try and do them tomorrow.
Need some solutions on raising my pH
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I haven't performed the tests yet. We got another winter storm and I am waiting for that to clear up before going outside. Will try and do them tomorrow.
OP
OP
JCOLE
Grower of the Small Polyps
Could be but it I am having a hard time thinking that the skimmer is a major player when it is sucking in fresh air right next to a large air pump. Anything is possible though. I really like those Regal 300Int skimmers. I plan on replacing my skimmer this year and more than likely will replace with that one.
Forgot to post my overnight results.Daytime was running 7.92 but waited until morning just before turning lights on to test PH and it was 8.9 something. Don't recall exactly yet it seems the algae base I have isn't performing enough photosynthesis to be the cause of why my PH has not gone up from averaging around 7.5. Assuming flow wasn't the catalysis depending on house CO2 then could it be due to maturing denitrification filter. Been trying to research the possibility that heterotrophic bacteria might utilize bound oxygen when nitrates and sulfates have been exhausted or better understand how denitrification exactly increases base. Thought it was purely a chemical process as with acidification during nitrification but could the bacteria be pulling the oxygen molecule from carbon dioxide therefore leaving behind carbonate. Would partially explain the rise in alkalinity although I now believe much of that due to my melting coral skeletons (Reborn) during nitrification. Very puzzling and hoping to figure this out.
You may be confusing #s in your post of pH and dKH.
It's virtually impossible to have a pH of 7.5 in a reef tank unless your tank has poor aeration, you are dosing something that lowers pH, or you house C02 is so high that it's unhealthy for humans and would cause health issues with extended exposure. If none of the above is true, you have a measurement issue.
In terms of Alk, your dKH will deplete as NO3 increases. However, once your tank matures and NO3 is consumed, that Alk will be returned to the tank.
Randy Holmes-Farley
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Consumption of nitrate adds alkalinity whether it is denitrifiation or simple consumption to form tissue.
I show the detailed process here:
Alkalinity Decline in the Nitrogen Cycle
One of the best known chemical cycles in aquaria is the nitrogen cycle. In it, ammonia excreted by fish and other organisms is converted into nitrate. This conversion produces acid, H+ (or uses alkalinity depending on how one chooses to look at it), as shown in equation 1:
(1) NH3 + 2O2 --> NO3- + H+ + H2O
For each ammonia molecule converted into nitrate, one hydrogen ion (H+) is produced. If nitrate is allowed to accumulate to 50 ppm, the addition of this acid will deplete 0.8 meq/L (2.3 dKH) of alkalinity.
However, the news is not all bad. When this nitrate proceeds further along the nitrogen cycle, depleted alkalinity is returned in exactly the amount lost. For example, if the nitrate is allowed to be converted into N2 in a sand bed, one of the products is bicarbonate, as shown in equation 2 (below) for the breakdown of glucose and nitrate under typical anoxic conditions as might happen in a deep sand bed:
(2) 4NO3- + 5/6 C6H12O6 (glucose) + 4H2O --> 2 N2 + 7H2O + 4HCO3- + CO2
In equation 2 we see that exactly one bicarbonate ion is produced for each nitrate ion consumed. Consequently, the alkalinity gain is 0.8 meq/L (2.3 dKH) for every 50 ppm of nitrate consumed.
Likewise, equation 3 (below) shows the uptake of nitrate and CO2 into macroalgae to form typical organic molecules:
(3) 122 CO2 + 122 H2O + 16 NO3- --> C106H260O106N16 + 138 O2 + 16 HCO3-
Again, one bicarbonate ion is produced for each nitrate ion consumed.
It turns out that as long as the nitrate concentration is stable, regardless of its actual value, there is no ongoing net depletion of alkalinity. Of course, alkalinity was depleted to reach that value, but once it stabilizes, there is no continuing alkalinity depletion because the export processes described above are exactly balancing the depletion from nitrification (the conversion of ammonia to nitrate).
There are, however, circumstances where the alkalinity is lost in the conversion of ammonia to nitrate, and is never returned. The most likely scenario to be important in reef aquaria is when nitrate is removed through water changes. In that case, each water change takes out some nitrate, and if the system produces nitrate to get back to some stable level, the alkalinity again becomes depleted.
I'm not confusing it. Well versed in both.
New build. No corals. No dosing. No supplementation. Just lots of media performing both nitrification and denitrification. Using an HM Digital PH-200 that is often calibrated and have never found it to not be calibrated. No clue how much CO2 in my house but will get around to buying a method of measuring it. Thought it might be an aeration issue but Randy brought up a good point that may disqualify that as to why it went up. Only change I made was increasing the flow through my filtration which is the same process which creates flow at the surface. Hence why I thought in my situation it PH went up. Has in the past. Nitrates did rise. Seems denitrification might have been affected by the increased flow and the most logical explanation.
My DKH is stable at 11. Top off is distilled water. Flow has been reduced and will test again.
7.5 NBS with 11dKH would put your CO2 at 4000ppm.
From a health perspective...
So if your feeling fine around your tank, chances are your home CO2 isn't near this level. So you have aeration or measurement issue.
A cup aeration test will help identify what's going on.
Also, if you dKH is stable (with no dosing as stated), the nitrogen cycle is not affecting dKH and hence not affecting pH.
If your NO3 rose by 50ppm your dKH would drop by 2.3dKH and the expected impact on pH would be as follows...keeping your CO2 levels at 4000.
As you can see, this would only be a ~0.1 drop in pH.
That's enlightening. Thought alkalinity lost during nitrification was not fully returned during denitrification which seemed odd to me since I thought of it as energy where it can only be transferred and not created or consumed.
Wasn't aware that nitrates consumed by algae would return carbonates.
Since I don't perform water changes and at the moment have little in the way of life forms that consume it (just snails) then I should remain neutral assuming my filtration is working as expected. However, I'm now more than ever believing that my use of Reborn might be melting since I had alkalinity reach 14 DKH shortly after raising it from brine to full salt using Reef Crystals and experimenting with tap water that in my area is high in minerals. Solution was using Seachem Acid Buffer to convert carbonates to CO2 until it lowered the DKH to 9. BTW, the expected PH drop was very temporary. Yet have since only added distilled and it has risen back to 11.
Considering CO2 is created during nitrification (as I understand it) then is it possible that it is reduced during denitrification. I'm not a chemist but try my best to grasp the fundamentals as it applies to filtration in order to best balance my system(s). Not exactly sure how CO2 is formed during nitrification but believe it is formed. Assumed it had something to do with carbonates and why I assume perhaps that denitrification depletes it.
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House temps at 72, tank at 78 and outside currently at 54. It's literally impossible for me to perform the cup test. Best I just buy a home air quality measuring tool. I feel fine around my tank. Still getting and air exchanger at some point.7.5 NBS with 11dKH would put your CO2 at 4000ppm.
From a health perspective...
So if your feeling fine around your tank, chances are your home CO2 isn't near this level. So you have aeration or measurement issue.
A cup aeration test will help identify what's going on.
Can only report what I'm seeing. Nitrates when flow is slow and I don't tinker remain below 5 ppm and phosphates under 0.25 ppm. Test kits is API and I know they aren't accurate but I'm not looking for precission. Just absense or presence and extreme measurements such as post cycle nitrates of 160 ppm or showing zero. Wasn't curious as to exactly how high but that it was high. For all intents and purposes. Filtration is working and I've measured my DKH with both API and Tropic Marin and again not going to be precise but I'm looking to stay above 7 and below 11. At some point I'll get better test kits but for the moement this is all experimental and holistically seeking results.Also, if you dKH is stable (with no dosing as stated), the nitrogen cycle is not affecting dKH and hence not affecting pH.
If your NO3 rose by 50ppm your dKH would drop by 2.3dKH and the expected impact on pH would be as follows...keeping your CO2 levels at 4000.
As you can see, this would only be a ~0.1 drop in pH.
A drop to from 25c to 12c will result in a pH increase of ~0.03. This is not significant for what the cup aeration test will identify...so you can go for the simple cup aeration test.
I don't think your pH issue is due to the tank cycling nor the Reborn substrate as its just effectively coral skeleton.
You either have an aeration problem (not enough flow in the tank) or a measurement problem.
Wasn't aware of that but at this point does it matter? My alk is at 11 and my PH at 7.9. Rather wait to test PH after a few days of returning to a slower flow as well as test all required parameters, again. If PH remained at 7.9 or basically above 7.8 then I'm golden because my main problem remains that I don't have consumers of alkalinity and was waiting until the PH stabilized above 7.8 so I can introduce coralline (added on Sunday) and corals which will come post establishment of coralline confirming system can support hard corals unless I get impatient which might likely happen. I also need to upgrade my light. That experiment failed miserably.
I'm only human but try my best not to be.
I think this is getting lost in translation. I no longer have a PH problem. Did at one time. Trying to better understand why. I posed a solution on aeration for which Randy provided information on why that might not be the case. At this point the conversation got off topic but it seems I'm learning and perhaps others might. Ecological systems being complex often have many variables affecting why something happens and better if we understand these variables and perhaps easier to understand and fix what went wrong. Hence me trying to understand why my PH was at 7.5. Wasn't because my measuring tool was wrong. That tool used is very accurate and was calibrated. Plus I used two different kinds of test strips to get a general confirmation. Again, not expected to be precision accurate but can show PH is lower than desired or somewhere in the vicinity of expected.
As for the Reborn, never said it was affecting my PH. Just raising my alkalinity. BTW, when PH was around 7.5 my alkalinity was around 14 DKH. One being a buffer of the other but not necessarily raising it. My understanding.
As for cycling, if I'm correct that nitrification increases CO2 (I've read this many times) then that was expected yet now wondering if denitrification lowers CO2. That latter part I'm unable to find or not understanding the literature. Wouldn't be the first time but I try.
Completely agree!
Just a note on coralline algae. It took my tank over 8 months before I really got good coralline growth...and I seeded it a couple different ways.
I've been trying to grow coralline since the mid 80s. LOL. My current light is a Kessil Tuna Sun set to full spectrum. I'm confident it will grow corals considering it's very intense and at full power should provide enough of the blues corals evolved to use at their depths. However, at the required intensity I'm guessing provides the best PAR my rocks have become covered in green algae. Not GHA. Not slime. Just the kind of coating an African cichlid tank would die for. Introduced an urchin on Sunday and got to mowing that lawn but seems to be more content on my gravel since that top layer is Reborn and lots of green growing there. Might need to turn the gravel and make it white again although currently going through a blackout to hopefully lower the algae but need to be careful because I don't want lose the coralline. Never ends. LOL
ying yang
2500 Club Member
Hi hope all is well,if predictive tx predicts to many words incorrectly then can turn it off.
On my Samsung phone I go to..
General management
Keyboard settings
Then turn off predictive tx.
Can Google it if yours is different or have a apple phone etc.
I know when get a new phone and predictive tx is on then it starts learning the common words you use most often then guesses/ predicts this is what you want so can just type first few letters then start next word as would of predicted and added in the previous word just from a few letters so makes typing faster but can often be wrong wo got to manually choose an option above keyboard if wrong.
My understanding of how it works anyway .
And if turn predictive tx off then will be exactly as you type and for me I often have lots spelling mistakes this way as touch the wrong button as letters so small but you can also make letters larger on keyboard if you want also I guess
Hope it helps ^_^
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Add bicarbonate should help
Adding a fan across tank or sump should also help
Adding a fan across tank or sump should also help
ying yang
2500 Club Member
Ummm very interesting read so thankyou everyone who contributed to the thread .
And now makes me wonder about my salifert nitrate test kit colour invetween 25 - 50 but closer to 50 and my tank is less than 1 meter away from a window but not in direct sunlight / the 2 windows next to the tank are always at least slightly open and I have very good surface agitation with 2 power heads facing water surface in dt and skimmer running 24/ 7
So makes wonder if all of above is reason/ or contributing why get such high nitrates .
But to be fair I feed decent amount of clams / shellfish to tank and my research / understanding is dry food like pellets etc raise p04 and fresh or live food raises nitrates plus only export I have is 10- 17% wc each week and skimmer 24/ 7 and not that many corals as taking it slow adding corals as first tank but not alot of algae on rocks even though high nitrates ( p04 = 0.25) and this last month I not cleaned glass once as doesnt need cleaning ^_^
Tank 9 months old and up until a month ago cleaned glass twice weekly,started with dry rock/ sand so maybe high nitrates nothing to do with flow/ surface agitation/ gas exchange etc and just simply newish tank that feeds heavy with 9 small- medium fish in 80g but you've given me plenty to think about and to test and watch out for so once again thankyou all ^_^
And now makes me wonder about my salifert nitrate test kit colour invetween 25 - 50 but closer to 50 and my tank is less than 1 meter away from a window but not in direct sunlight / the 2 windows next to the tank are always at least slightly open and I have very good surface agitation with 2 power heads facing water surface in dt and skimmer running 24/ 7
So makes wonder if all of above is reason/ or contributing why get such high nitrates .
But to be fair I feed decent amount of clams / shellfish to tank and my research / understanding is dry food like pellets etc raise p04 and fresh or live food raises nitrates plus only export I have is 10- 17% wc each week and skimmer 24/ 7 and not that many corals as taking it slow adding corals as first tank but not alot of algae on rocks even though high nitrates ( p04 = 0.25) and this last month I not cleaned glass once as doesnt need cleaning ^_^
Tank 9 months old and up until a month ago cleaned glass twice weekly,started with dry rock/ sand so maybe high nitrates nothing to do with flow/ surface agitation/ gas exchange etc and just simply newish tank that feeds heavy with 9 small- medium fish in 80g but you've given me plenty to think about and to test and watch out for so once again thankyou all ^_^
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