Low Alkalinity

DRC Archive General Saltwater Discussion
1

So here is my dilemma. I have just tested everything, and my calcium is at 400ppm, my Magnesium is 1260ppm, and my Alkalinity is 5.2 dKH. My pH is 8.0.

My organics are zeroed out.

I have probably a half a dozen small size stony corals and probably 4 or 5 large stonys- a large red montipora, a chalice and some torch and frogspawn corals and a large galaxia coral.

I don’t know very much about salt water chemistry but I was wondering if anyone had any advice on raising Alk.

I monitor my levels bi-weekly, and I see the same thread of alk being low. I have Red Sea Foundation ABC+ and I know how to use it but do not want to until I have more information.

2

Your alk is always that low? It’s not going to kill anything being that low but a sudden change will. I would just add some slowly over weeks to bring it up. Also magnesium. Be careful if you raise alk the calcium will tend to drop so I would add calcium too. If you use salt in buckets to do water changes make sure you mix the salt up in the bucket. The elements tend to settle toward the bottom causing a drop in elements during the first few uses. Then at the bottom the elements will be higher.

3

That is low in relation to Ca, have you been adding anything? like Tim said double check your salt supply and i wouldn’t change alk more then .5 every other day…

4

what test kit how old? but, regardless, you possibly need a hannah checker to confirm. i have one, if you wanna borrow it. in smyrna.

5

Paul you still have equipment left? Did you set a tank up again?

6

well, if your test results for alk prove to be correct, and it is indeed low, you can just add some baking soda to boost the alk more and the PH a little. Arm and Hammer baking soda(Sodium BiCarbonate) adds alk carbonates and a little PH boost, which would help. you have some stoney corals and monti caps that grow well and use a lot of alk.

Myself, i use a 50/50 mix of Arm and hammer Baking soda(sodium BiCarbonate) and Arm and Hammer washing soda(Sodium Carbonate) for a better alk and PH boost. just what my tanks need. Arm anf Hammer Super Washing soda(sodium Carbonate) gives a stronger boost to PH, for tanks that have low PH problems.

I buy them both at PathMark grocery store. Baking soda in 1 pound boxes in the baking department.

and Arm and Hammer Super Washing Soda(sodium Carbonate) in the laundry detergent department, in a 4 pound box.

thats my mix. you can adjust the mix to suit your ALK/PH needs.

7

no tim, no tank setup. i still have plenty of equipment though.

8

I would double check the kH again bc that is very low.

[quote=“kaptken, post:6, topic:6475”]
well, if your test results for alk prove to be correct, and it is indeed low, you can just add some baking soda to boost the alk more and the PH a little. Arm and Hammer baking soda(Sodium BiCarbonate) adds alk carbonates and a little PH boost, which would help. you have some stoney corals and monti caps that grow well and use a lot of alk.

Myself, i use a 50/50 mix of Arm and hammer Baking soda(sodium BiCarbonate) and Arm and Hammer washing soda(Sodium Carbonate) for a better alk and PH boost. just what my tanks need. Arm anf Hammer Super Washing soda(sodium Carbonate) gives a stronger boost to PH, for tanks that have low PH problems.

I buy them both at PathMark grocery store. Baking soda in 1 pound boxes in the baking department.

and Arm and Hammer Super Washing Soda(sodium Carbonate) in the laundry detergent department, in a 4 pound box.

thats my mix. you can adjust the mix to suit your ALK/PH needs.[/quote]
I’ve heard of some people baking theirs first, is that necessary?

9

I have a Red Sea test kit that I use and its fairly new, less than a year old. I tested everything twice (except the calcium, i just hate that test)

You say to use Pure A&H Baking Soda, but how much? If my levels are at 5.2 and I have a 75gallon tank with a roughly 16 or 17 gallons refugium, how much would I add? I noticed that the corals grow but only a certain few are really taking off and the others are lagging behind. Like my Acans (who don’t do very well in my tank anyway, i have no place to put them that they aren’t being burned away by the lights) and some of my acros and birds nests aren’t taking off. But I have two red Montiporas that are huge and growing and a chalice that is doubling every couple of months. I want some of the other more branching SPS to grow like the digitata and the branching monti i have.

10

Maybe have your water tested by lfs or some one local. To make sure they are accurate before you go too far. We used to have water test party’s lol it was fun we could start that again. Paul your still invited GolfC I’m in Smyrna and have test kits galore and would help out if interested.

11

Well, if you want to figure out how muck baking soda to add you can use the handy dandy “Reef Calculator” to figure it out. I like the TRADITIONAL version.

http://reef.diesyst.com/chemcalc/chem_calc3.html

Yes, you can bake the baking soda to drive off some moisture in the bonds and convert the Bi-Carbonate to sodium carbonate. or, if you are lazy, like me, just buy some as the Arm and Hammer Super Washing Soda. it works better.

http://reefkeeping.com/issues/2006-02/rhf/index.php

just dont use anything else, like, 20 mule team Borax, or any other brand of detergent booster, those are an entirely different chemical. They will mess you up, big time.

12

I have retested it on a Salifert test kit, and it is even lower than I thought it was. its at 4.8. My corals are FINE they have polyps out, are growing like crazy, and everyone has color. I don’t know why my ALK is so low…

13

How often do you change the water? What salt do you use?

14

typically I change the water weekly, but I didn’t change any last week so two weeks since the last one. and I used Instant Ocean Reef Crystals.

15

Mix some fresh water up and test it. It should be around 10 dkh make sure your salinity is correct. I think after that you’ll know what’s up. If you have been changing the water with Iorc that often I really think you salinity is low or your test is off. Very odd that two test kits are saying it though. Just a stupid question but I have to ask your measuring dkh not meq/l right? I’m sure it is dkh I’m not too familiar with meq

16

Reef crystals usually read 10-12dkh and 440-450 calcium on a fresh mix for me.
If you are not dosing calcium and alk the fast growing corals will eat it up. water changes will only increase a small amount, never getting back to the 10dkh since it is constantly being used and only a small % being replenished.

17

The uptake of Ca and Alk, by “stony” type coral, coralline algae, etc. in a reef system is 20 ppm Ca to 50 ppm(2.8dKH) Alk(CaCO3), which is a ratio of 2 pts Ca to 5 pts Alk (2:5). Equal doses of any two part supplements are designed to provide the same ratio’s. So, they will all work but, I have found that the brand name products are going to be more expensive. I use one of the BRS (Randy’s) recipes. I considered using the Dow flake, etc., but just can’t get my head wrapped around the fact that something that is used in your driveway to melt snow and ice is going to be pure enough to add to an aquarium.

Saturated kalkwasser also contains this same ratio, @ ~ 800 ppm Ca(2pts.) to 2,000 ppm CaCO3(5pts.). It also has the added benefit of utilizing some of the CO2 in your system, which may help keep your pH in line. Even though I’m using a two part recipe, I also still use the kalk in my dosing regimen. The problem with kalk is that it’s limited in its ability to keep up with a high demand due to the fact that you’re limited to how much you can add to RO/DI water(2tsp.), and your evaporation rate. You can boost that to 3 tsp. with the addition of vinegar, but that also adds a carbon source, and potentially other issues.

If you’re using a “reef” grade of salt mix, i.e. Reef Crystals, I’d make sure the salinity is right, by measuring it using a calibrated (@35ppt) refractometer, or metering device. This will ensure you are adding enough Ca, Alk and Mg when you do your WC’s. With normal WC’s mixed to a salinity of 1.026, I’ve never had to add Mg, using this type of salt mix.

If you find your SG is good, I’d make up some of Randy’s recipe #1, using 1 1/8 cups of baking soda to a gallon of RO/DI water (a hand held blender works well for mixing this), use the calculator below, and Randy’s recipe 1 in the alk drop down, to determine your dose. It’s possible that your WC’s may be enough to keep up with your Ca needs, but I’d get some Calcium Chloride from BRS, and have it ready to start dosing that as well(1 1/4 cup of Calcium Chloride to 1 gallon of RO/DI water). Same calculator, and Randy’s recipe #1 applies for Ca too.

Add the recommended Alk solution to get your alk where you want it, i.e. 8dKH, etc., if needed add the Ca solution to get your Ca where you want it, i.e. 420, etc., and then start testing your parameters to develop a base line of usage. Once you know how much Ca and Alk your system uses, over a few days, do the math to determine how much you will need to dose each day.

http://reef.diesyst.com/flashcalc/flashcalc.html