Where do you keep your Alk, and Why??

[Heidi]

Where do you try to keep your Alkilinity? Why do you Try and keep it there?
Just wondering :)
Heidi

[CableGuy]

I usually float around 8, but try to keep it around 9. Its what I read on the interwebz.

[Heidi]

I wish I could get it and keep it at 6, I think the ocean is right close to that and I wonder why more people don't keep it lower. I guess this is why I made this thread. Just wanted some input. :big_grin:

[CableGuy]

It is in part a safety net. The lower the number, the smaller that net.

[MizTanks]

I keep mine at 9. Why because for me it gives me a little swinging room without being to high/low. My corals seem to be liking it as well.

[joe ringbloom]

try to keep my around 7 right now been having issues with it in mid 6's my duncuns wont open had to put in my nano where its in mid 7's and they open up. stonies like mid 7's from what ive earned in my tanks

[larryandlaura]

Mine is at 8. I like a little room for it to swing up or down. I'm going to ry to run our tank at 7-8.

[rosebud161616]

I keep mine at 10. I don't want it to go below 8, over 12 at any time, so if I aim for 10 I have a safety net. With dosing 2 part I need that net. This may change when I get my calcium reactor setup.

[bigbill]

i keep mine at 9 - 10

[rmalone]

I shoot for 7 which is very close to natural. I just tested and was just over 5, yea I've been lazy. If you run to low, like my 5dkh you really run the risk of ph dropping FAST.

I shoot for 7 because I run vodka and high ph will burn sps tips if your at ultra low nutrient levels. On a normal tank, exactly where you keep alk isn't that big of a deal. 6.5 up to 12 isn't going to kill anything all by it'self. The most important thing is to pick a spot and stay there, drastic fluctuations are what screws things up.

[rosebud161616]

I'm just curious, I see a lot of people mention that the ocean's alkalinity is 6-7dKH. I'm curious where everyone is finding this info. Whenever I have researched this, I find that current studies show that the alkalinity is slowly decreasing, but currently slightly over 8.0dKH.

[binford4000]

I'm just curious, I see a lot of people mention that the ocean's alkalinity is 6-7dKH. I'm curious where everyone is finding this info. Whenever I have researched this, I find that current studies show that the alkalinity is slowly decreasing, but currently slightly over 8.0dKH.

Most of the test kits have statements quoteing the oceans alk level of being in the 7 to 8 dkh range.I personaly try to keep an 8 dkh but are starting to lean to matching what my salt mixes at after several e-mails with britewell on this very subject.It was explained to me that your salt mix will do best for the inhabitants if you try to match the specs provided with the product.It was recomended to me that I should test the newly mixed water and try to maintain the alk,cal and ph of that mix.Just some FYI

[Chris L]

I keep mine as steady at 9dkh as possible.

Also see: http://www.reefkeeping.com/issues/2004-05/rhf/index.php

[MizTanks]

double post

[Jim Z.]

I'm running my tank's alk at around 8-9 dKh. My sulfur reactor tends to pull the alkalinity to 6 so running alk at slightly higher levels seems to work best fr me right now. The SPS corals seem to prefer these alk levels too!....Jim Z.

[cephalotus]

I shoot for 8.4 because that is what AquaVitro recommends.

[CalmSeasQuest]

10.5 dKh. Higher Alk limits diurnal pH swings and increases CO2 solubility in CaRx.

[schminksbro]

Higher alk will also smoke certain corals especially maricultured or wild acropora.;)

10.5 dKh. Higher Alk limits diurnal pH swings and increases CO2 solubility in CaRx.

[reefhead]

Higher alk will also smoke certain corals especially maricultured or wild acropora.;)

I try to keep mine around 9, then it does not do any damage if it goes up and down one.

Wild acro and maricultured do just fine at high alk. It is mainly an issue of how quickly it changes in my experience.

I routinely see the best colors in my sps at around 12dkh, calc 450, ph 8.4 However i do not advise this because it is setting your tank up for alk swings. Which even if it does not kill anything, it is still extremely departmental to coral growth.

The most senstive coral I have noticed to sudden alk swings is higher end z and ps which are normally pretty hardy.

[schminksbro]

Taking a maricultured acro from the ocean at 6.5-7dkh and dropping it in a tank at 9-11dkh constitutes an alk swing. I deal with hundreds of maricultured acros and it has been my personal experience that they tend to maintain color and health upon introduction when alk is kept at lower (near natural) levels. Some acros are much, much more sensitive to alk swings than others. With availability of methods to maintain stable alk I personally see no value at running our alk levels much higher than natural ocean levels. 15 years ago yeah, but not anymore.

I try to keep mine around 9, then it does not do any damage if it goes up and down one.

Wild acro and maricultured do just fine at high alk. It is mainly an issue of how quickly it changes in my experience.

I routinely see the best colors in my sps at around 12dkh, calc 450, ph 8.4 However i do not advise this because it is setting your tank up for alk swings. Which even if it does not kill anything, it is still extremely departmental to coral growth.

The most senstive coral I have noticed to sudden alk swings is higher end z and ps which are normally pretty hardy.

[CalmSeasQuest]

Andy,

Do you think it's the higher Alk level per se, or Alk swings that pose the greatest problems (assuming no Carbon dosing)?

I run Alk toward the higher end of the range (~10 dKh) but with very little variation and have had no problems with SPS.

I'd be curious to know what values firms such as LiveAquaria/DD use in their holding an QT systems. I'm sure the shock of going from 8 to 10+ dKh could have adverse affects.

[schminksbro]

Andy,

Do you think it's the higher Alk level per se, or Alk swings that pose the greatest problems (assuming no Carbon dosing)?

I run Alk toward the higher end of the range (~10 dKh) but with very little variation and have had no problems with SPS.

I'd be curious to know what values firms such as LiveAquaria/DD use in their holding an QT systems. I'm sure the shock of going from 8 to 10+ dKh could have adverse affects.
I think swings are definitely the most detrimental. However when acquiring a newly imported coral whether it be wild or maricultured you are taking a risk introducing it to a carbonate level that is substantially higher than NSW levels. In essence you are subjecting the coral to an immediate alk swing which in today's day and age is totally avoidable. IMHO running your alk at 10,11, or even 12dkh is an extremely antiquated method. Afterall why would we possibly want to deviate from NSW levels when we don't have to and we know better? There are many aspects of ocean life that we cannot (at this time) duplicate but alk and calcium levels don't fall under that category. When possible I prefer to approximate natural conditions that the animals we keep have grown accustomed to over millenia.

[jimsflies]

Here is an excerpt from a Randy Holmes-Farley article on water parameters:


Unlike the calcium concentration, it is widely believed that certain organisms calcify more quickly at alkalinity levels higher than those in normal seawater. This result has also been demonstrated in the scientific literature, which has shown that adding bicarbonate to seawater increases the rate of calcification in Porites porites.4 In this case, doubling the bicarbonate concentration resulted in a doubling of the calcification rate. Uptake of bicarbonate can apparently become rate limiting in many corals.5 This may be partly due to the fact that both photosynthesis and calcification are competing for bicarbonate, and that the external bicarbonate concentration is not large to begin with (relative to, for example, the calcium concentration).

For these reasons, alkalinity maintenance is a critical aspect of coral reef aquarium husbandry. In the absence of supplementation, alkalinity will rapidly drop as corals use up much of what is present in seawater. Most reef aquarists try to maintain alkalinity at levels at or slightly above those of normal seawater, although exactly what levels different aquarists target depend a bit on the goals of their aquaria. Those wanting the most rapid skeletal growth, for example, often push alkalinity to higher levels. I suggest that aquarists maintain alkalinity between about 2.5 and 4 meq/L (7-11 dKH, 125-200 ppm CaCO3 equivalents), although higher levels are acceptable as long as they do not depress the calcium level.

More can be read here (http://reefkeeping.com/issues/2004-05/rhf/index.php).

I agree with Andy in terms of alk/pH swings with newly added stock...maintaining sea water alkalinity levels will be one less variable to deal with. But if someone is not adding new stock and wanting to maximize growth of stoney corals, there may be some logic to keeping an elevated alkalinity level due to the fact that growth rates have been shown to improve as a direct relationship to alkalinity (bicarbonate) concentration.

[MizTanks]

Love this info!!!

[ROGERWILCO357]

do corals like sps acro's grow faster in higher or lower alk? has anyone noticed a spike in growth when at a certain level?

[rosebud161616]

I notice spikes in growth when my alk is stable, not so much at a certain level.

[marc49127]

I have found that with my acro's they are more sensitive to lighting than alk levels. I try to keep my tank at 9.5-10 and have had no problems introducing sps to my tank at that level. I just start them out on the sand and work them up gradually. I notice brighter colors and better growth at this level too. My belief is that it is an aquarium not an ocean so it will have a different personality.