Need help understanding

[saltyfins]

I have a 125 mixed tank, and that alk usually runs 7.8, and I keep bumping it up with baking soda...my question is this, and I have read a lot of threads here, but it's really hard to understand a lot of the answers. I set up a 32 gallon bio cube a month ago. Has 1 18 lb rock that is cycled, nice an purple, came from my other tank, that's been going 15 years. used live bagged sand, and old media from other tank, as well as used turbo 900 to start it. It has 1 small duncan, which now has 3 heads, a paly and some xenia I put in, also from other tank. I just checked the alk on the 32, and it's at 8. why is this already so low? I did a water change 4 days ago, and I run 1.026 on both tanks, using reef crystals. it's also low on N03, which is coming in at 2..Red Sea test kit. Just curious, because at one time, my alk was at 12 and stayed there, never could get it down. again, I get it on the 125, but not the 32. Any help understanding what could cause this, would be great. Thanks!

 

[Jekyl]

Coraline and bacteria consumed the alk most likely. Less water means faster swings.

 

[saltyfins]

Coraline and bacteria consumed the alk most likely. Less water means faster swings.

so the coraline from the rock? There's none so far on any of the glass. Now the larger tank, it's bananas with the coraline, it's on EVERYTHING...I am not a fan. Thank You @Jekyl

 

[PeterC99]

Coraline and bacteria consumed the alk most likely. Less water means faster swings.

Spot on!

 

[Randy Holmes-Farley]

Bacteria do not consume alk, except those processing ammonia to nitrate. if nitrate is steady at any level, bacteria are not an alk sink.

 

[saltyfins]

Bacteria do not consume alk, except those processing ammonia to nitrate. if nitrate is steady at any level, bacteria are not an alk sink. Attach files

amonia is 0, Nitrites are also 0 but Nitrates, are 2. which also seems far too low, for a new tank. Or is that backwards thinking? I have some little green algae on sand and glass, looks like LHA, except very short.

 

[Randy Holmes-Farley]

I expect there is just some calcification going on, either biological or abiotic or both. Not any big deal and if alk is still 8 dKH, I wouldn't bother dosing anything.

 

[saltyfins]

I expect there is just some calcification going on, either biological or abiotic or both. Not any big deal and if alk is still 8 dKH, I wouldn't bother dosing anything.

Thank You, Randy. I'll just keep up on the water changes.

 

[blasterman]

Randy, Nitrate is almost always being consumed in a tank to some extent by anaerobic activity or corals, or chaeto, or xenia, or water changes, or nuisance algae. The fixation of Nitrate is almost always in process. Because your nitrate is steady at a number does not mean Nitrate is not being produced. It simply means its being consumed as fast as its being produced, and this has some degree of equilibrium in all tanks.

Nitrite conversion has to go somewhere, right? Ammonia to nitrite has to go somewhere, right? If Nitrate production in a healthy tank were an actual zero some input what are nitrite to nitrate bacteria doing??????.

My point being, tank biology other than corals is always consuming alk to a variable degree. Having rapid changes in alk consumption is normal....not an oddity.

 

[truepercs]

I would also double check new salt water that you are using for water change. What level is Alk before adding to do the water change.

 

[saltyfins]

I would also double check new salt water that you are using for water change. What level is Alk before adding to do the water change

 

[saltyfins]

I will have to test that. Dang! it doesnt even mention it on the bucket, but on website says 8-12 DKH. I am consistantly 7. something in my tank. seems that would have been the most obvious thing to do, test mix first ;Shy

 

[Randy Holmes-Farley]

My point being, tank biology other than corals is always consuming alk to a variable degree. Having rapid changes in alk consumption is normal....not an oddity.

That is all correct, except your last conclusion above, which is not.

Production of nitrate from ammonia consumes 4.5 dKH per 50 ppm nitrate produced.

Consumption of nitrate in any process except sulfur denitrification adds 4.5 dKH per 50 ppm of nitrate consumed. That is true whether the final product is ammonia, N2, or nitrogen-containing organic tissue.

Thus, there is only a net change to alkalinity if nitrate is rising or falling. If nitrate is steady at any level, there is no impact on alkalinity from the nitrogen cycle, regardless of the flux from fish food to ammonia to nitrate to something else.

 

[truepercs]

I will have to test that. Dang! it doesnt even mention it on the bucket, but on website says 8-12 DKH. I am consistantly 7. something in my tank. seems that would have been the most obvious thing to do, test mix first ;Shy

I mentioned because that is where I am @... I only have a few sps test corals, and the coralline has not yet really started. But I want to see if Alk is starting to be consumed. The Apex doser was set up to do 1 gallon a day water change, when water changes can not keep stable. I will have to go to next step. (Which of course that will be a good thing)

 

[truepercs]

amonia is 0, Nitrites are also 0 but Nitrates, are 2. which also seems far too low, for a new tank. Or is that backwards thinking? I have some little green algae on sand and glass, looks like LHA, except very short.

Since we are @ similar stages... FYI...Currently my Nitrates are also around 2.

In addition to some test sps, a fist size tort and encrust-er.. a Fiji leather was the first coral added on 5/09. The polyps are not as extended as much as in the local aquarium shop that I purchased it from. I suspect that the nitrates are lower and the light source may be a bit higher than in the store. Although the Kessil lights were started @ 20% and is slowly ramping up.

The fish load is minimal, as in your case, I do not see feeding raising it much in my case.

My approach is to get Nitrates up a little higher to 4/5 ppm with potassium nitrate. ( 4/5 is my current target selected until aquarium tells me where it wants to be ) I think this should benefit both the test corals, and yellow leather at least that is the hope...

I am trying to keep it simple, not sure if working to get nitrates a little higher is pre-mature or not but it is the path I have chosen, At this point things are going well.


Seeing Randy's comment is helpful...
"Thus, there is only a net change to alkalinity if nitrate is rising or falling. If nitrate is steady at any level, there is no impact on alkalinity from the nitrogen cycle, regardless of the flux from fish food to ammonia to nitrate to something else."

Currently testing @
My Alk is testing @8.0 dKH with Hanna tester in aquarium and the fresh salt water in the auto water change is IO and is @10.0dKH

I hope your experience is going well with the new aquarium!

 

[truepercs]

"Thus, there is only a net change to alkalinity if nitrate is rising or falling. If nitrate is steady at any level, there is no impact on alkalinity from the nitrogen cycle, regardless of the flux from fish food to ammonia to nitrate to something else."

May be helpful for both of us...

Randy As Nitrates raise what direction does the ALK go?

 

[Randy Holmes-Farley]

"Thus, there is only a net change to alkalinity if nitrate is rising or falling. If nitrate is steady at any level, there is no impact on alkalinity from the nitrogen cycle, regardless of the flux from fish food to ammonia to nitrate to something else."

May be helpful for both of us...

Randy As Nitrates raise what direction does the ALK go?

Rising nitrate means alk depletion.
Falling nitrate means alk addition.

Dosing nitrate at steady (or falling) nitrate level means adding alkalinity.

In all cases, it takes a 50 ppm nitrate change to cause a 4.5 dKH alk change (except if water changes are messing with alk or nitrate levels).

 

[saltyfins]

Since we are @ similar stages... FYI...Currently my Nitrates are also around 2.

In addition to some test sps, a fist size tort and encrust-er.. a Fiji leather was the first coral added on 5/09. The polyps are not as extended as much as in the local aquarium shop that I purchased it from. I suspect that the nitrates are lower and the light source may be a bit higher than in the store. Although the Kessil lights were started @ 20% and is slowly ramping up.

The fish load is minimal, as in your case, I do not see feeding raising it much in my case.

My approach is to get Nitrates up a little higher to 4/5 ppm with potassium nitrate. ( 4/5 is my current target selected until aquarium tells me where it wants to be ) I think this should benefit both the test corals, and yellow leather at least that is the hope...

I am trying to keep it simple, not sure if working to get nitrates a little higher is pre-mature or not but it is the path I have chosen, At this point things are going well.


Seeing Randy's comment is helpful...
"Thus, there is only a net change to alkalinity if nitrate is rising or falling. If nitrate is steady at any level, there is no impact on alkalinity from the nitrogen cycle, regardless of the flux from fish food to ammonia to nitrate to something else."

Currently testing @
My Alk is testing @8.0 dKH with Hanna tester in aquarium and the fresh salt water in the auto water change is IO and is @10.0dKH

I hope your experience is going well with the new aquarium!

we'll have to stay in touch, so we can also pick eachothers brain!

 

[truepercs]

Rising nitrate means alk depletion.
Falling nitrate means alk addition.

Dosing nitrate at steady (or falling) nitrate level means adding alkalinity.

In all cases, it takes a 50 ppm nitrate change to cause a 4.5 dKH alk change (except if water changes are messing with alk or nitrate levels).

Thank you Randy...

we'll have to stay in touch, so we can also pick each others brain!

Will do...