Low alkalinity, what does this mean and what should I do?

[Hannahhhh]

I have a pretty new tank and my alkalinity is low. I’m new to the hoby and I’m struggling to understand what exactly this means, why it happened, and how to fix it. Can you guys help me out? If you don’t have time to explain stuff, I would be thankful if you could include a link to a good explaination. The stuff I’m reading online just has me more confused. 

 

Temp: 80.2

Ammonia: 0

Nitrite: 0

Nitrate: ~15

Alkalinity: 6.5 dKH (0.5dKH resolution)

pH: 8.2

 

I have a fluval evo 13.5 and a MAME design protein skimmer.

I have a tiny clownfish and a small cardinalfish. One Mexican turbo snail, a few hermit crabs, and a pom pom crab. 

I also have a small Xenia and a small spotted mushroom coral. 

 

[billygoat]

Simply put, alkalinity is a measurement of your system's capacity to resist sudden drops in pH. Alkalinity is maintained in your aquarium's water by various compounds, but the most important ones to aquarists are carbonate or bicarbonate compounds, hence the common term "degrees of carbonate (or as the abbreviation goes, "karbonat", from German) hardness" (dKH). The higher your reading of dKH, the more resistance your tank has against dips in pH. Tracking your dKH is important because pH affects the amount of calcium in the water that is available to corals and other reef-building organisms, with higher pH allowing for a higher concentration of calcium in the water. For this reason many reef aquarists that are adding calcium to their systems are careful to maintain a certain level of dKH. This helps to maintain a consistently high pH, which ensures that the water in the aquarium remains saturated with calcium to encourage rapid growth in stony corals.

 

Now, with that being said, the "proper" level for alk can vary wildly from tank to tank. Your test kit, for example, may say that a reading of 6.5 dKH is "low", but what it means is that that reading would be low for the average reef aquarium - i.e. a tank with a lot of stony corals and other calcifying organisms, where demand for calcium is high. In a tank such as yours, where there are only a few soft corals and the demand for calcium is low, a reading of 6.5 dKH is probably perfectly fine.

 

Remember that in the last analysis, the most important indicator for whether a given parameter is too high or too low is the health and appearance of your livestock. If you observe your tank frequently to get a feel for what your animals "should" look like, you'll know at once when something is amiss - and that's when your testing kit can come in handy to help you figure out what you have to change to keep your system in balance. On the other hand, when everything appears to be doing well, chasing the "perfect" number for a given parameter is likely to do more harm than good!

 

TL;DR don't worry about your alk until you get more corals. Hope this was helpful! 😄

[jservedio]

Hannah, the most common reason for low alkalinity when you don't have stony corals using it up is simply improperly mixed salt water. Are you mixing your own saltwater or buying it from the LFS? If you aren't mixing your own, you will probably want to start doing that since it is going to be far more consistent, and consistency is most important.  If you are mixing your own - make sure you are doing it properly and that you are measuring your salinity accurately. Pick one salt brand and stick with it long term unless you have a compelling reason to switch. All of them will be perfectly fine (I just use Instant Ocean because it's the cheapest available to me and works fine).

 

While 6.5 dKH isn't all that low, it is certainly a red flag in a tank that really shouldn't be using up Ca and Alk. The biggest issue with inconsistently mixed water is one week you may end up with water with 6dKH and the next week 13dKH and those wild swings aren't going to be good for anything.

 

If you want a really, really good understanding of Alkalinity, Calcium, and Magnesium - read this: http://www.reefkeeping.com/issues/2002-04/rhf/feature/index.php

[Hannahhhh]

Billygoat and jservedio, thank you so much for your answers. I really appreciate you taking the time to help me out. I feel relieved. I was paying a lot (like way too much) for my LFS to mix my saltwater for me in hopes of avoiding such issues, but I will promptly startl mixing my own. 

 

I can tell that my fish, snail, and crabs are all doing well and acting happy. Coral is much harder for me to judge since I’m inexperienced. My Xenia is happy enough since I can easily see that it’s open, but I have no clue if my mushrooms are happy. Honestly they could be slowly dying and I might not know. It looks the same as the day it arrived from live aquaria, which is both concerning and relieving. I’m not making it any worse (phew), but I’m also not making it any happier. 

[jservedio]

20 minutes ago, Hannahhhh said:

Billygoat and jservedio, thank you so much for your answers. I really appreciate you taking the time to help me out. I feel relieved. I was paying a lot (like way too much) for my LFS to mix my saltwater for me in hopes of avoiding such issues, but I will promptly startl mixing my own. 

 

I can tell that my fish, snail, and crabs are all doing well and acting happy. Coral is much harder for me to judge since I’m inexperienced. My Xenia is happy enough since I can easily see that it’s open, but I have no clue if my mushrooms are happy. Honestly they could be slowly dying and I might not know. It looks the same as the day it arrived from live aquaria, which is both concerning and relieving. I’m not making it any worse (phew), but I’m also not making it any happier. 

How are you measuring salinity currently? One of the first things you should definitely invest in is a good refractometer or probe - you can pick up a good refractometer from Bulk Reef Supply or Marine Depot for about $35. Those swing-arm hydrometers are pretty inaccurate. If your salinity is off, all of your other parameters are going to be off as well. Water coming form the LFS is likely a lower salinity than you want since they typically mix their water for fish-only tanks which normally run at a lower salinity (also explains low alkalinity) - plus it's cheaper for them to use less salt.

 

You definitely want to be running your reef with a specific gravity of 1.026, which is the same as 35ppt. Until you get your own RODI machine, buy RODI water from the LFS or jugs of distilled from Walmart (should be less than $1/g regardless of how you do it) and a quality salt should be around $0.20-$0.35/gallon depending on the brand. Mix it according to the instructions and once it's mixed and up to the proper temperature, measure the salinity. If the salinity is low, add more salt 1 tsp at a time until you are up to 35ppt. If salinity is high, add in a little fresh water until you are at exactly 35ppt.

 

If the salinity in your tank is low, instead of topping off with RODI, you can top off with fresh salt water until the salinity is up where you need it. If the salinity needs to come up a lot, mix the salt water 50:50 with RODI as you top off to make the increase happen over a longer period of time.

 

[billygoat]

1 minute ago, jservedio said:

How are you measuring salinity currently? One of the first things you should definitely invest in is a good refractometer or probe - you can pick up a good refractometer from Bulk Reef Supply or Marine Depot for about $35. Those swing-arm hydrometers are pretty inaccurate. If your salinity is off, all of your other parameters are going to be off as well. Water coming form the LFS is likely a lower salinity than you want since they typically mix their water for fish-only tanks which normally run at a lower salinity (also explains low alkalinity) - plus it's cheaper for them to use less salt.

 

You definitely want to be running your reef with a standard gravity of 1.026, which is the same as 35ppt. Until you get your own RODI machine, buy RODI water from the LFS or jugs of distilled from Walmart (should be less than $1/g regardless of how you do it) and a quality salt should be around $0.20-$0.35/gallon depending on the brand. Mix it according to the instructions and once it's mixed and up to the proper temperature, measure the salinity. If the salinity is low, add more salt 1 tsp at a time until you are up to 35ppt. If salinity is high, add in a little fresh water until you are at exactly 35ppt.

 

If the salinity in your tank is low, instead of topping off with RODI, you can top off with fresh salt water until the salinity is up where you need it. If the salinity needs to come up a lot, mix the salt water 50:50 with RODI as you top off to make the increase happen over a longer period of time.

 

^All this stuff! Salinity is huge and I strongly recommend you get a good hand refractometer at the very least. I actually prefer the analog models over digital ones because they last forever with proper maintenance; mine is more than 20 years old and still works perfectly fine. Definitely worth the investment.

 

Also you will want to perform smaller, more frequent water changes rather than larger, infrequent ones during the first few weeks after you make the switch from LFS water to home-mixed saltwater, just to make sure you don't suddenly send your parameters wildly out of control.

[Hannahhhh]

5 minutes ago, billygoat said:

^All this stuff! Salinity is huge and I strongly recommend you get a good hand refractometer at the very least. I actually prefer the analog models over digital ones because they last forever with proper maintenance; mine is more than 20 years old and still works perfectly fine. Definitely worth the investment.

 

Also you will want to perform smaller, more frequent water changes rather than larger, infrequent ones during the first few weeks after you make the switch from LFS water to home-mixed saltwater, just to make sure you don't suddenly send your parameters wildly out of control.

 

14 minutes ago, jservedio said:

How are you measuring salinity currently? One of the first things you should definitely invest in is a good refractometer or probe - you can pick up a good refractometer from Bulk Reef Supply or Marine Depot for about $35. Those swing-arm hydrometers are pretty inaccurate. If your salinity is off, all of your other parameters are going to be off as well. Water coming form the LFS is likely a lower salinity than you want since they typically mix their water for fish-only tanks which normally run at a lower salinity (also explains low alkalinity) - plus it's cheaper for them to use less salt.

 

You definitely want to be running your reef with a specific gravity of 1.026, which is the same as 35ppt. Until you get your own RODI machine, buy RODI water from the LFS or jugs of distilled from Walmart (should be less than $1/g regardless of how you do it) and a quality salt should be around $0.20-$0.35/gallon depending on the brand. Mix it according to the instructions and once it's mixed and up to the proper temperature, measure the salinity. If the salinity is low, add more salt 1 tsp at a time until you are up to 35ppt. If salinity is high, add in a little fresh water until you are at exactly 35ppt.

 

If the salinity in your tank is low, instead of topping off with RODI, you can top off with fresh salt water until the salinity is up where you need it. If the salinity needs to come up a lot, mix the salt water 50:50 with RODI as you top off to make the increase happen over a longer period of time.

 

Thank you both. I was using my Red Sea marine care test kit. I will try to invest in a refractometer moving forward. What do you guys think about this one? Worth buying? 

[jservedio]

Get one that comes with 35ppt calibration fluid, or add some calibration fluid to the cart.

[Clown79]

What salt brand are you using because each one mixing to different levels and has different mixing instructions

 

are you using a refractometer or hydrometer to read salinity? A refractometer is far more accurate.

 

What is your salinity being mixed to because if its low 1.022-1.024, your parameters will be lower.

 

For a reef you want either 1.025 or 1.026 which will give you higher parameters.

 

 

Your salt may be mixing low, therefore the alk will be low.

 

Always stir the dry sand to get it fully mixed before using it, then make a batch of new salt water. 

 

Test alk once the water is clear.

 

If your salt mixes low you have 2 options.

 

1. Use another salt with better parameters

2. Dose the newly mixed water with 2 part.

 

There is also the case where if the salt mixes low magnesium, you can run into issues with unbalanced ca and alk.

 

New tanks often have instability, new sand and rock can use up alk as well and then usage will drop off and stabilize.

 

So letting us know

 

Salt brand

How you mixed it

Your salinity how you test it

 

 

I highly recommend you research water chemistry. It's very important

 

https://www.advancedaquarist.com/2002/11/chemistry

 

http://reefkeeping.com/issues/2007-03/rhf/index.php

 

 

BRS has a ton of videos on YouTube that are highly recommended.

[Hannahhhh]

On 4/5/2019 at 5:04 PM, jservedio said:

Get one that comes with 35ppt calibration fluid, or add some calibration fluid to the cart.

Do you have a specific one you recommend? 

[jservedio]

21 hours ago, Hannahhhh said:

Do you have a specific one you recommend? 

Whatever is cheapest and comes in a resealable bottle - you only need a few drops with a refractometer to calibrate it. Resealable is best since you can check to make sure it's accurate from time to time without having to buy another bottle of solution.

 

I have a Pinpoint probe, so I have a bottle of American Marine solution that came with the probe. A big bottle is like $8.

[MrObscura]

I personally hate refractometers, not because they are innacurate or anything but I found reading them to be a Pita. 

 

I got the ice cap digital tester and it's quick, convenient, and accurate. And as a bonus also gives you a temp reading. It's a bit more pricey but woth it imo. 

[Naekuh]

On 4/8/2019 at 9:09 AM, MrObscura said:

I personally hate refractometers, not because they are innacurate or anything but I found reading them to be a Pita. 

 

I got the ice cap digital tester and it's quick, convenient, and accurate. And as a bonus also gives you a temp reading. It's a bit more pricey but woth it imo. 

Have you seen the feedback on that unit? Its horrible...

 

Here is amazon:

https://www.amazon.com/IceCap-Digital-Pocket-Salinity-Temperature/dp/B07BBSRKZ1

 

Here is BRS:

https://www.bulkreefsupply.com/salinity-temperature-digital-pocket-tester-icecap.html

 

Both of them list that unit as horrible.  

 

I was honestly looking for a digital salinity meter, but i gave up as it seems most of them are in accurate

Even the milwakee i hear is not perfect, and has issues, so i just end up sticking with a refactormeter + calibration solution, because its usually solid and it seems to calibrate nicely with my  hydrometer.

[jservedio]

7 hours ago, Naekuh said:

Have you seen the feedback on that unit? Its horrible...

 

Here is amazon:

https://www.amazon.com/IceCap-Digital-Pocket-Salinity-Temperature/dp/B07BBSRKZ1

 

Here is BRS:

https://www.bulkreefsupply.com/salinity-temperature-digital-pocket-tester-icecap.html

 

Both of them list that unit as horrible.  

 

I was honestly looking for a digital salinity meter, but i gave up as it seems most of them are in accurate

Even the milwakee i hear is not perfect, and has issues, so i just end up sticking with a refactormeter + calibration solution, because its usually solid and it seems to calibrate nicely with my  hydrometer.

I've got the American Marine Pinpoint Salinity Monitor and I've had it about 5 or 6 years now and it's bombproof. I calibrate it every time I change the battery (1-2 years) and it's never once been more than 1/2 a PPT off even after changing the batteries. I'll spot check it against my refractometer every few months and never once had a mis-reading.

 

The biggest issue people have with most salinity probes is that they are idiots who can't be bothered to read the instructions. They are extremely sensitive to temperature and when you have cold probes touching warm water, it takes a minute or two of sitting still in the water for the probes to come up to temperature. If you drop a cold probe into your tank, it's going to read at least 2 PPT high and over the next minute or two will start to drop down to a stable, correct reading. You also have to watch for air bubbles getting under the probe - so just give it a shake after it's up to temperature.

 

Most probe-style digital salinity monitors actually are measuring the conductivity, which changes quite a bit with temperature. When your probe is at 65f and your water is 80f, that's a big difference. Here's how much that difference affects conductivity:

[MrObscura]

19 hours ago, Naekuh said:

Have you seen the feedback on that unit? Its horrible...

 

Here is amazon:

https://www.amazon.com/IceCap-Digital-Pocket-Salinity-Temperature/dp/B07BBSRKZ1

 

Here is BRS:

https://www.bulkreefsupply.com/salinity-temperature-digital-pocket-tester-icecap.html

 

Both of them list that unit as horrible.  

 

I was honestly looking for a digital salinity meter, but i gave up as it seems most of them are in accurate

Even the milwakee i hear is not perfect, and has issues, so i just end up sticking with a refactormeter + calibration solution, because its usually solid and it seems to calibrate nicely with my  hydrometer.

I wouldn't call 3 stars horrible. I usually prefer at least 4 stars on products I purchase. But I looked into this product before buying it and the vast majority of issues revolves around using the little attachment cup that used to come with the unit. Ice cap no longer even includes it. In fact ice caps is just a rebrand of a model that never included such a thing. As for the rest I'd bet most didn't bother recalibrating it if need be. 

 

Without the cup its accurate.