Running alk at NSW level

[Lavey29]

I've noticed my alk has dropped from 8dkh to low 7dkh now during the week. I've got a ton of coraline growth and the corals are really thriving. I'm debating whether to allow the alk to remain at 7dkh with current dosing or increase my dosing and bring it back to 8-8.5dkh. Seems like the tank really loves the NSW level at 7. Have not seen any problems with about 25 SPS frags and mini colonies. I do use coral pro salt so that is a swing on water changes every 3 weeks about 15% water change.

Any thoughts on staying with the lower alk?

 

[fishski13]

I run the Aquaforest reef salt and there method with NSW levels. My Alkalinity is constantly around 7-7.7ish and I like what I am seeing. Also only have to dose every few days to when it drops closer to 7 to help bring it up.

 

[Lavey29]

I run the Aquaforest reef salt and there method with NSW levels. My Alkalinity is constantly around 7-7.7ish and I like what I am seeing. Also only have to dose every few days to when it drops closer to 7 to help bring it up.

Now I have read running lower alk means running lower nutrients also ULNS set up? I've got very sufficient nutrients in my tank at 10 nitrates and .1 phosphate so will that conflict with lower alk at all?

 

[fishski13]

Now I have read running lower alk means running lower nutrients also ULNS set up? I've got very sufficient nutrients in my tank at 10 nitrates and .1 phosphate so will that conflict with lower alk at all?

I dont think so, I run about 8ish nitrates and .03ish phosphates at a given time and with a NSW alkalinity and havent see much interference.

 

[mdb_talon]

I'm not saying it is good/bad/otherwise, but in my personal experience I have to dose much more running at 9 dkh to stay stable than I had to at 7dkh to stay stable. This could be caused by a couple things but one of the most logical is corals using more....thus growing faster. Of course it also could have been precipitating(however I never have any evidence of that and believe that is a very unlikely explanation).

It could be because my ph stays higher when I dose more and the pH drives the growth moreso than the alk level? It is definitely possible, but in any case at least in my experience growth appears visually faster running at 9 and is backed up by how much alk/calc I need to dose when I run at a higher all compared to lower.

Again just my experience and whether true in other tanks I can't say, but even if it is true in general that in itself is only a benefit if you want faster growth.

 

[Spare time]

Now I have read running lower alk means running lower nutrients also ULNS set up? I've got very sufficient nutrients in my tank at 10 nitrates and .1 phosphate so will that conflict with lower alk at all?

Its more that if you run an ULNS you need to have lower alk levels (i.e. nsw levels)

 

[Nano sapiens]

One of the main reasons that you'll often see ~9 -10 dKh as a recommendation is that it lies somewhere in the middle of the typically given acceptable reef range (7 - 12 dKh). Since many reef aquariums experience alk swings, being in the middle gives one a better chance of catching the alk swing before it goes into the danger zone (especially on the low side).

I typically run between 8 and 9, but I too notice that the corals look 'happiest' at around 7.8 - 8.0. Perhaps because they are more relaxed from not expending the energy to grow as fast as they would at 9 or 10.

 

[homer1475]

I do not run ULNS(NO3 = 15 to 20, PO4 = .1 to .2), but run closer to NSW @ 7 to 7.5.

I have had less issues with acro's at NSW levels then I ever did above 8DKH.

It's really a matter of choice, and if your looking to squeeze optimal growth out of your corals. My tank is fairly full, so to curb the constant pruning, I run closer to NSW so my corals aren't growing like crazy, but at a normal rate.

 

[X-37B]

I run my alk at 7 on 3 systems.
Ca 420
Mag 1350
No3<10
Po4<.1
Works well for me and have never seen the need to run higher alk.
My 20g nano for reference.

 

[Lavey29]

I run my alk at 7 on 3 systems.
Ca 420
Mag 1350
No3<10
Po4<.1
Works well for me and have never seen the need to run higher alk.
My 20g nano for reference.

These are my levels currently too

 

[X-37B]

These are my levels currently too

Over the years I have found 7dkh to be more forgiving than higher 9+ alk levels.
Never had an issue if it creeps up. Also I have had it go to 5.5 with no visible issues observed.
Aveage ocean alk is 6.5 contrary to what many coral vendor/experts will tell you.

 

[Lavey29]

Over the years I have found 7dkh to be more forgiving than higher 9+ alk levels.
Never had an issue if it creeps up. Also I have had it go to 5.5 with no visible issues observed.
Aveage ocean alk is 6.5 contrary to what many coral vendor/experts will tell you.

Do you think since we are trying to mimic the ocean, alk just naturally gravitates towards that 7 number also instead of when we try to artificially increase it to higher range with dosing and pro salt?

 

[Lavey29]

I do not run ULNS(NO3 = 15 to 20, PO4 = .1 to .2), but run closer to NSW @ 7 to 7.5.

I have had less issues with acro's at NSW levels then I ever did above 8DKH.

It's really a matter of choice, and if your looking to squeeze optimal growth out of your corals. My tank is fairly full, so to curb the constant pruning, I run closer to NSW so my corals aren't growing like crazy, but at a normal rate.

Good info, thanks

 

[X-37B]

Do you think since we are trying to mimic the ocean, alk just naturally gravitates towards that 7 number also instead of when we try to artificially increase it to higher range with dosing and pro salt?

No. Alk is dependent on useage and dosing.
Dont dose it will fall.
We dose to keep the levels we want.

After 30 years I get good growth and healthy corals maintaining NSW alk levels.

We ran super high alk levels in the late 80's early 90's and had some nice looking systems too.

 

[Lavey29]

Its more that if you run an ULNS you need to have lower alk levels (i.e. nsw levels)

So you match the alk to the nutrients level instead of matching nutrients to your preferred alk level.

 

[Lavey29]

No. Alk is dependent on useage and dosing.
Dont dose it will fall.
We dose to keep the levels we want.

After 30 years I get good growth and healthy corals maintaining NSW alk levels.

We ran super high alk levels in the late 80's early 90's and had some nice looking systems too.

Yes I'm aware we need to dose to maintain a certain level but I was curious if it naturally wants to be at that 7 range to match NSW but instead we artificially raise it to a preferred higher level for aforementioned reasons? I guess what I'm referring to is there is a point where your tank finds perfect balance and stability. You always know what your parameters will be even before you test. Each tank is unique and what is ideal for one may be almost completely opposite for another. Some run alk at 7 some run it at 10. Do you think a tank gravitates over time to be more inclined with NSW numbers overall or does it not matter as long as what you have going works for your particular set up?

 

[Spare time]

So you match the alk to the nutrients level instead of matching nutrients to your preferred alk level.

The idea is that if you provide the corals with elevated alk, they will be able to build their skeletons faster. However, they also need the nitrogen and phosphate to be steadily available in a slightly larger quantity (or frequency) to build the soft tissue alongside the skeleton. It seems the skeletal growth can "outgrow" the soft tissue in ulns with elevated alk, leading to the famous burnt tips

 

[Brymac1]

If you and your tank are happy at 7 then keep it at 7

 

[Randy Holmes-Farley Verified Community Expert]

Yes I'm aware we need to dose to maintain a certain level but I was curious if it naturally wants to be at that 7 range to match NSW but instead we artificially raise it to a preferred higher level for aforementioned reasons? I guess what I'm referring to is there is a point where your tank finds perfect balance and stability. You always know what your parameters will be even before you test. Each tank is unique and what is ideal for one may be almost completely opposite for another. Some run alk at 7 some run it at 10. Do you think a tank gravitates over time to be more inclined with NSW numbers overall or does it not matter as long as what you have going works for your particular set up?

Alk doesn't want to be at any particular level.

It naturally declines, but the decline is faster at higher alk.

So eventually without any dosing, the decline due to calcification slows and stops as the alk gets down into the 6 dKH range. Alk will drop further from other acid additions, such as nitrification of ammonia.

 

[Lavey29]

Alk doesn't want to be at any particular level.

It naturally declines, but the decline is faster at higher alk.

So eventually without any dosing, the decline due to calcification slows and stops as the alk gets down into the 6 dKH range. Alk will drop further from other acid additions, such as nitrification of ammonia.

Ok, thanks, perhaps that explains why mine has settled in at 7 but I'm sure my dosing is helping it maintain that level also.

But other things might affect the alk level also right such as magnesium or PH or salinity?