Reason to Run Low Alk?

[Colinpologordon]

I run low alk (6-6.7 dKh) simply because it ended up there a long time ago and I chose to focus on just keeping it stable, rather than raising it.

I’ve also had pretty good success with SPS at those levels. I don’t think that has anything to do with it being low, there’s just no incentive to change it.

Some pictures to support my anecdotal account: 7 months growth from June ‘19 to January ‘20. The little Walt Disney from the first picture is sitting on the rack in the second pic. Cut a frag from it and put the frag in its old spot.

Totally agree I usually run my tank around seven but I’m looking after some high end corals for a friend who usually runs his around 8.5 anyway his new tank is nearly ready so i have suggested we both get our tanks to 8 to give the corals the best chance when they go back . I definitely feel they grow and look better at 7dkh

 

[BigRich]

All really interesting information. I know we as consumers have different goals/levels than a vendor but when you look at the success vendors like WWC have running higher ALK or the BRS investigates video on running higher alk equaling more growth I would have thought more people would be in the 8.4-8.8 ALK range. I'm right around 8.1, sometimes dropping to 7.9 or up to 8.2, according to my trident. Everyones input gives me thoughts about dropping to around 7.5 for my frag tank to experiment. I appreciate all the input.

 

[Lousybreed]

Ahhhh @jda love the growth photo of German blue. It got me thinking and you have a valid point about growth reference. Here is my low boy 4’x2’ frag tank full of purple digitata and German blue. 3 years ago I bought a frag of each. It is actually my fuge and the corals grow under 5,500k light. I also have the birdsnest from the same time. I have filled a five gallon bucket full and still have my main colony and this one in my frag tank (basketball size) I think alk is less important than water circulation, available nutrients, and lighting. But after those I do think alk is important. But when you get the four right, your growth can be spectacular. I estimate I have grown over 24 cubic ft of these three corals alone. @vetteguy53081 can attest to the huge amount of these corals I have.

 

[vetteguy53081]

Ahhhh @jda love the growth photo of German blue. It got me thinking and you have a valid point about growth reference. Here is my low boy 4’x2’ frag tank full of purple digitata and German blue. 3 years ago I bought a frag of each. It is actually my fuge and the corals grow under 5,500k light. I also have the birdsnest from the same time. I have filled a five gallon bucket full and still have my main colony and this one in my frag tank (basketball size) I think alk is less important than water circulation, available nutrients, and lighting. But after those I do think alk is important. But when you get the four right, your growth can be spectacular. I estimate I have grown over 24 cubic ft of these three corals alone. @vetteguy53081 can attest to the huge amount of these corals I have.

These pieces are monsters. I have that birdnest which wouldn’t fit in a 2.5 gal bucket. Here it is today
And im about to get much more from him IF WEATHER EVER COOPERATES and they quit surprise scheduling me at work

 

[pharazon]

I'm assuming you are properly acclimating them to new tank. I don't think going from high to ow or low to high will be an issue as long as you drip acclimate the corals.

I have never once drip acclimated. Straight from 8-10 dKH water, into a harsh dip, and into my 6 dKH water. Never had a problem.

What Tenuis is upper right of your WD?

RRA Orange Passion.

 

[spidercrab]

I have never once drip acclimated. Straight from 8-10 dKH water, into a harsh dip, and into my 6 dKH water. Never had a problem.



RRA Orange Passion.

Yup I have seen this time and time again which just about proves that alkalinity hardly matters. Its just the sudden pH changes from overdosing that causes coral mortalities and it has led THE ENTIRE hobby to be obsessed with tight alkalinity control and constant worry about alkalinity.

 

[eidels]

Interesting discussion! I’ll add that Alk consumption can change relatively quickly and cause both dangerously high as well as low levels. When coralline and coral mass, light and nutrients are critical mass, consumption outstrips supply; alk plummets. When nutrients get a bit too high then cyano or other algae will cover the coraline, as well as generalized decreased calcificationconsumption goes down resulting alk spikes

 

[Sean Fitz]

Idk, I gotta say I have seen people lose a lot of corals from alkalinity swings, and from overly low alk. It is pretty obvious to anyone who doses that the corals use alkalinity. RE dosing, alkalinity is one part of a 2 part calcium buffer system - at the end of the day it is carbonates and bicarbonates bonding with calcium to develop stony coral skeletons, and the acid concentration in the water needs to be as such to allow that chemical reaction. If you have a mature tank with crushed coral or sand, and a ton of live rock (that is actually old coral skeletons and not concrete or something) you may have sufficient buffering capacity within the tank. Tanks with crushed coral or aragonite sand tend to have higher alk and pH absent dosing.

How to Grow Corals Quicker: Effects of Various Alkalinity Concentrations on Rates of Zooxanthellae Photosynthesis

For corals to grow at their best, many chemical and physical conditions must be optimized. Dana Riddle examines the effects of varying levels of dissolved bicarbonates on coral photosynthesis and growth.

www.advancedaquarist.com

One thing not mentioned that BRS has been getting at in their investigates series lately is the effect of water flow having a larger impact on coral growth than even lighting. The more I observe my tank the more I believe there is merit to this as well. I have also seen videos and experiments to illustrate that as well.

 

[Cory]

Idk, I gotta say I have seen people lose a lot of corals from alkalinity swings, and from overly low alk. It is pretty obvious to anyone who doses that the corals use alkalinity. RE dosing, alkalinity is one part of a 2 part calcium buffer system - at the end of the day it is carbonates and bicarbonates bonding with calcium to develop stony coral skeletons, and the acid concentration in the water needs to be as such to allow that chemical reaction. If you have a mature tank with crushed coral or sand, and a ton of live rock (that is actually old coral skeletons and not concrete or something) you may have sufficient buffering capacity within the tank. Tanks with crushed coral or aragonite sand tend to have higher alk and pH absent dosing.

How to Grow Corals Quicker: Effects of Various Alkalinity Concentrations on Rates of Zooxanthellae Photosynthesis

For corals to grow at their best, many chemical and physical conditions must be optimized. Dana Riddle examines the effects of varying levels of dissolved bicarbonates on coral photosynthesis and growth.

www.advancedaquarist.com

One thing not mentioned that BRS has been getting at in their investigates series lately is the effect of water flow having a larger impact on coral growth than even lighting. The more I observe my tank the more I believe there is merit to this as well. I have also seen videos and experiments to illustrate that as well.

They did a flow video somewhere whch showed iirc that increasing flow didnt increase calcification much compared to slower flow. However i think their slow flow wasnt slow enough imo.

 

[Sean Fitz]

You're right, I must be thinking of another video as the experiment I saw was a low frag tank with direct flow on the corals using a gyre. BRS was completely indirect flow with vortechs. Their first experiment actually showed considerably more growth though (tank 1 to 3). There was clearly inconsistencies somewhere else though, perhaps nutrient levels

 

[SeaDweller]

I have never once drip acclimated. Straight from 8-10 dKH water, into a harsh dip, and into my 6 dKH water. Never had a problem.

for real man.

 

[JOKER]

in almost 175+ frags I bought last year, not one death has occurred when I plop them into my ~7.5 dkh tank from tanks running alk from 8.5-9.5+.

Are these acro frags?

 

[SeaDweller]

Are these acro frags?

Of course.

 

[Daniel@R2R]

Ahhhh @jda love the growth photo of German blue. It got me thinking and you have a valid point about growth reference. Here is my low boy 4’x2’ frag tank full of purple digitata and German blue. 3 years ago I bought a frag of each. It is actually my fuge and the corals grow under 5,500k light. I also have the birdsnest from the same time. I have filled a five gallon bucket full and still have my main colony and this one in my frag tank (basketball size) I think alk is less important than water circulation, available nutrients, and lighting. But after those I do think alk is important. But when you get the four right, your growth can be spectacular. I estimate I have grown over 24 cubic ft of these three corals alone. @vetteguy53081 can attest to the huge amount of these corals I have.

That's amazing!

 

[Graffiti Spot]

This is a good thread. I do believe that alk being constant is not needed. I dose once a day so it swings each day, doesn’t hurt anything. May change once things really grow in but copps did it this way on an older tank.
I generally shake my head at growth pictures using digi as proof but I love some German blue jda! And lousybreed, why are you growing fields of that stuff? Just for refugium type filtration from the corals? Awesome pics.
The only digi that is actually tough to grow is the metal polyp digi that Adam had a long time ago. I had a piece of this strain not from him but it could have been the same original colony and I couldn’t get it to form a colony, mainly because new growth just got knocked off and lost by big fish. I have wanted to find this digi to try again for a long time but haven’t seen it since. I am actually sad I lost it. Tried growing it for two years watching new branches go missing from angels. Really unique digi!

 

[Rjmul]

I agree with @W1ngz. One benefit of running lower Alk may be lower salt costs as you would not have to pay the extra for the elevated level salt mixes.

That's not real. The more expensive salts are lower in alk

 

[pharazon]

That's not real. The more expensive salts are lower in alk

Agreed. Haven’t had a bucket of Tropic Marin Pro mix higher than 7 dKH in years.

 

[zafink]

So I just switched to tropic Marin pro, bought from BRS. I was planning on dosing alk because of the 7dkh that is labeled (and that it seems most people end up around)

To my surprise, dKH measured at 8.9 with Hannah. All other measurements are where I like to keep them as well. I measured again alk again just to be sure, 8.9 again. I find it a little odd that my batch is measuring this high considering that most people on the forum are getting much lower readings.

Well, less dosing for me I guess! Just found it interesting

@Rjmul @pharazon

 

[Max93]

I have been doing a lot of reading, and realized that:

With high alk, you need higher nutrients
With low alk, you need lower nutrients
That sound right?

with that said, I have kept alkalinity stable at 8.3, no matter what time of day and ALWAYS kill my acros. I use salifert, refractometer, yada yada. My error was not importing enough nutrients. You have to keep in mind that in the LFS these animals get fed a bunch more than in our homes. So higher alk makes sense.

I’m now going to try 7.0-7.5 alk and hopefully that works. My nitrates are always at 5 and my phosphates are typically .01 to .04. I feed THREE times a day.

 

[jda]

That seems to be a popular belief, but probably a gross oversimplification. Unless you are driving residual N and P very low (like below natural seawater levels) with media or chemicals, there is no need to keep alk low to limit calcification.

I think that all of this is just based on some bad evidence from back when people wanted to do Zeo and true ULNS, but that has not been popular with the masses for at least a decade. Those that do use this do indeed usualy keep their alk lower than most.

I keep my alk around 7.0 because that is what is in the ocean and I like to stay around there.

If your acropora are constantly dying, then alk at 8.3 is not the reason.