Reason to Run Low Alk?

[SteadyC]

Generally, I run lower alk in a lower nutrient environment. Higher alk in a low nutrient environment tends to result in burnt tips. The problem with gleaning just a single parameter or thing to emulate is that it's just that, one of many parameters/things that are being used and won't necessarily result in the same/identical results as the tank (or vendor) you're emulating.

I agree with this approach, lower nutrients, lower ALK, lower PAR. Everything working together. and match consumption possibilities. If you have higher nutrients, than consider higher ALK, and higher PAR.

i run 7 myself, and I do have low nutrients.

i think one of the reasons to run between 7 and 8, is if something does happen, your buffer, 2 part, kalk, calcium reactor, whatever, stops working for whatever reason, you can drop to say 7, where you hopefully catch it before it gets too much lower. Just a failure buffer,

 

[ether]

A lot of really interesting thoughts/opinions. When I thought of posting this I figured most ppl would be running ALK around 8.6/higher due to the BRS video of running a higher Alk causing more sps coral growth from awhile back. Honestly surprised to see so many running lower/more natural alkalinity levels. I personally believe my sweet spot is around 8-8.1 in my DT, but so many posts about running near 7 makes me want to experiment in my frag tank. Really interesting points of view from all!

This. The experiment brs did was pretty convincing. The cost of dosing might be slightly higher, so I guess you have to decide if that's worth the vast increase in growth to you.

 

[Lousybreed]

It might be important to explain where the fear of higher alk and "burnt tips" comes from. In a nutshell, when building blocks are very low, then calcification happens faster and tissue cannot grow as fast since they need new building blocks to make new organic tissue. The skeleton grows faster than the tissue can grow and after a while, the exposed skeleton gets stressed and the tissue stops grow. True "burnt tips" are a result of growth, not existing tissue dying back - this is something else.

This usually only ever happened when people used media/chemicals to lower building blocks lower than Natural Sea Water levels... which is nearly impossible without using media/chemicals. Keeping the alk lower would somewhat growth-limit the calcification process where it would not outgrow the tissue.

Keep in mind that the ocean is about .1N, .005P and 7.0 dKh. Ultra Low people wanted to get lower than this for some reason... so they had to keep their dKh lower too.

Calcification decreases as N and P rise, so having lower dKh will not really harm anything since growth is slower anyway. The amount of slowing growth depends on the species where as some might not slow down much and others might nearly stop at moderate level.

In general, I don't think that it matters much unless you are looking to be at a top 10% level for growth and color. I also do not think that dKh swings or changes account for nearly the amount of issues that they get blamed for... I have never had issues moving frags, buying or selling. At best, if a coral is weak and otherwise not healthy, it might be the final punch, but not too much more than this.

Great info on the burnt tips! 100% dead on. I think it’s important people understand these issues. I actually ran into this issue when I first started. I was overly concerned about nutrients so I had a fuge with a 150w HPS bulb. Grew cheato like crazy. N and P were undetectable and I had corals with burnt tips everywhere.

As for coral growth I think after a certain level of N and P growth goes down. But holding everything constant besides N and P levels (which can be raised by heavier feeding, removal of macro algae, running the skimmer less than 24/7) if you go from low nutrients to let’s say 5ppm N and 0.15ppm P, you will see increased growth rates. I have done this experiment twice now (finally removed all macro algae and not ever going back to low nutrients) and my calcification rates we higher with high nutrients. I would have to search through my notes to find the data but it was between 50-100% faster growth for my WD and for a upscales I was testing against. Since I was weighing the frags, I am sure there was a bit of uncertainty in the actual data. I have been nutrient heavy now for 3 months and my calcium reactor went from running 60ml/min at a ph of 6.5 to now I am at 120ml/min at 6.38....and this in the end is the most concrete evidence I need on nutrients and growth rate.

 

[Sean Fitz]

Ime higher alk with higher nutrients can produce more growth. With ultra low nutrients and high alk, you get white tips as someone mentioned earlier as the calcified structure is growing taster than tissue can maintain pace. Low nutrients and low alk will pysh the coral to push out brighter colors, as absent nutes it relies on the zoanthalline algae to provide energy. And it takes a while for those colors to emerge, so consistent parameterd are key. A coral may survive wild swings but it wont thrive in those conditions. Ive only ever lost frags that were damaged in transit, and possibly furthered by temperature swings shipping in winter. I run 7-8dkh, fwiw. I feel like alk swings also lead to cyano blooms and poor calcetrous algae buildup -

 

[Sean Fitz]

I also think the redfield ratio also plays a factor. My corals use way more alk when phosphate is below .08ppm, which means they are growing more, but only when nitrate is also below 25ppm.

 

[pharazon]

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.

 

[Zeal]

I run a steady 8.0



here a pic of a fellow reefer I get my stuff form that runs his tank at 5.0-6

I used to run 10.5-11ishhhhh back when I started and noticed I had a hard time holding that number without a doser

so I switched to Red Sea blue bucket and now I can hold a steady 8 all day with my doser

 

[satiger1]

I stopped doing all measurements except salinity for more than a year. One frag I got from local shop started slow death. So did alk and CA test. ALK turned out to be 4.8 at that time.

Couldn't believe myself. Repeated few times, same result. Ordered different test kit from Amazon, tested , showed 5.1. During last one year period (no measurements time) I have had no issues with coral growth and coloration. Didn't have any algae breakout either.

But started dosing alk and CA. It's stable around 6.8 - 7. Never crosses 7. To me alk is over rated .

 

[Scott.h]

For my sps I try not to let it go higher then 7.8, but only because my N and P stay undetectable (not on purpose just a low stocked in fish). And many sps are deep water corals. My par is 175, and my tank just runs better this way. Maybe not the fastest for sure, but healthy. Light, parameters, and alk all are relative to each other.

 

[watdachuck]

IMO and experience running above 9 has not worked well for me. I think that has been because of my fixation with keeping the tank as clean as possible. Ever since I brought my target Alk into the 7-8 range my SPS have grown faster, and brightened up! I also no longer see those burnt tips that used to plague me.

At the end of the day it is just the type of tank you are running, and with what equipment. If the nutrients are available for the taking a higher alkalinity might work out very well. It just depends....

 

[HMpops]

There’s a lot a great info in this thread. I’d like to add, and I live close to WWC and Top Shelf (TSA). Some of the comments relative to the levels BRS/WWC videos. There are a couple important distinctions between a coral farm and hobbyist. Primarily being...they are removing frags/corals all day, everyday. Obviously, because they’re selling them. Thus, their numbers come from their experiences trying to maintain consistency throughout their systems. 8.6 in the case of WWC. Having that slightly elevated number allows room for a slight drop.
Another reference in this thread was in NSW at 7.0. As hobbyist, our aquariums are not natural. Meaning, our parameters change. As much as we fight to keep them stable, they change.
One of the things you’ll find in the BRS series is how they tried to communicate...farms have a team of employees checking their parameters and feeding every hour on the hour. That’s not practical in the hobby.
Last point, there’s also a difference between keeping corals alive, and keeping cost down. Verses trying to maximize growth. There’s a balance we all have to find for ourselves. A farm needs to maximize growth. I, for example, want to control my growth.

 

[jda]

I would caution people not to take too much stock in how fast somebody thinks that something is growing unless that person has a lot of experience at different levels and can quantify them... there are just too many other variables. Before we had good test kits, we all used to run about 10 dKh, 450 calcium, had a "clear" result on a N test kit (most people had sand beds back then that would destroy nitrates to just a trace) and nobody knew what their P was. We all thought that we had good growth. We had no idea what would happen when we got better test kits and could actually stay near NSW and stuff grew many times faster. We found out that we did not know.

For my part, I can grow a normal acropora under NSW type conditions from a 1/2 frag to about a softball in 6-9 months and then a basketball in two years. This means a frag-down and tank reboot in about three years. Some, even faster.

I will say that lighting plays a larger role in this than pure tank parameters, but you have to be at least competent.

I am not saying that fast growth is everything... it is CERTAINLY not and rebooting sucks, but just to be cautious of hobbyist anecdotes about growth if you are interested in growth. Most people mean well, but do not know what they do not know.

As for our tanks not being natural, of course they are not 100%, but these animals originated from there and it might be a good idea to do the best that you can to keep it natural over the long term. Zoos don't put a grizzly bear in a polar bear enclosure full of ice and just say "it is not nature, so screw it..."

Here is 5 months growth on a ORA German Blue Digitata (this is a more difficult one for a digi, in case you do not know - meaning: people kill them and they don't grow as fast as others). It has added a few more inches since the recent photo. This is in alk at 6.8 to 7.0 and NSW level N and P. It will likely be about the size of a dinner plate in a year. This is what I mean by fast growth, so it can be understood by readers.

 

[Kevan Sharp]

I’ve been doing a lot of reading/research on reasons for running higher alk(8.4-9.0) and their seems to be benefits in coral growth but I’ve wondered what about keeping lower alk levels of 7.5-8.0. In talking to some major online vendors I’ve been told we keep our sps Alk at;
8.6
7.5
9
8.1-8.4

Four different vendors that are pretty large and been in business for awhile with a pretty wide range of Alk levels. Any thoughts on benefits/reasons for running lower Alk? I won’t even get into par recommendations for the same coral from different vendors, from 300 PAR all the way to 450 PAR on the same piece. Just seems like A LOT of different opinions out there and I’m always interested in the why. Wondering what others think of keeping Alk low vs higher?

Back in the day of my college classes on water quality, alkalinity is used to 'buffer' the water's capacity to handle variation in pH. the end goal is pH. Getting the buffering capacity that is necessary to maintain stable pH is by alkalinity. That being said, I am unsure if alkalinity level is a critical water quality factor other than it needs to be high enough to handle the chemical interactions that will challenge pH variations (oxidation/reduction, etc).
I follow the Red Sea parameters, which recommends alkalinity at 11.0. I have run it at 7.5, 8, 9, 10 and 11. It doesn't seem to matter, but it might make a difference in the long haul. I've noticed that the automated systems have probes for pH, not for alkalinity.

 

[HMpops]

Let me quality my point about NSW. My point was, in nature, parameters do not fluctuate like our aquariums. Thus, parameter goals can be slightly different, than NSW, for farms...and hobbyist.

 

[goliwala]

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+.

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.

 

[EMeyer]

I'd quibble over the phrasing. 7 isnt low alk, its normal alk. See: the ocean.

I've seen nothing but problems above 8. I read lots of theories about interactions between alk and nutrients, but since these theories are usually based on misunderstandings about how corals build skeletons (you cannot have skeleton growth without tissue growth, it isnt possible), and I've seen little evidence of these interactions, I find them pretty unconvincing.

My experience is high alk kills corals, and while I know some people manage to keep them alive and even thrive at higher alk, I await evidence its a benefit. I mean, lots of people run their reefs at unnaturally low salinities too, or unnaturally high Magnesium. Doesnt mean its actually helping anything.

 

[VillainzReefExotics702]

I like my alk around 8-9 personally I get good results

 

[SeaDweller]

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.

Proper acclimation for me is temp float, dip, and drop it in. I’ve never once lost any acro from that. Drip acclimation is excessive and not necessary, but you stick to what works for you.

 

[Charlie’s Frags]

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.

What Tenuis is upper right of your WD?

 

[Reefer40b]

I have always kept my frag system around 7, and 7 being the target. Corals always looked good for me and grow great!