High Mag, Low Alk, perfect Cal. Please help me understand before dosing!

jherrin215

jherrin215

GO COLTS!!
Hello All! I have had this tank up and running for about 10 years now. It has thrived at times, survived at times and about everywhere in between. I have decided that it is time to right the ship and make this a thriving setup as it has all the potential! I have started testing with new Red Sea Pro test kits and as I hoped, nitrates, nitrites and ammonia were all 0. Here is where I need guidance :

PH 7.8 last week, started dosing alk portion of 2 part 3 nights ago to slowly raise alk levels. This morning ph 8.2
Alk last week, 4.5 dKH, this morning 6.3 after a couple small doses of sodium bicarbonate 2 part solution
cal - 450
temp - 76
SG - 1.025
Magnesium - 1560ppm

I don't even know how to begin dosing when my mag is over target, alk is well below target and calcium is nominal! I use instant ocean reef crystals salt. I will test the saltwater, which is mix in 55 gallon batches so it sits for lengths of time before all being used and post those test results here as well! Thanks in advance to anyone willing to help me understand why my numbers are so skewed and to assist me in developing a plan to get things leveled out!
 
Things just get out of whack.
Dose what you need & not what you don't.
Take it slow do not rush.
Fast changes are not a good thing
Alkalinity will change daily depending on more than 1 thing.
This is the most important parameter, so you will have to monitor it & understand how much you need to dose daily.
PH is its own animal & you should NOT chase #'s, let it settle on its own.
 
Thanks for the reply. Is there a way to get magnesium down or will it drop on it's own? Also once I get everything in range would it be normal to have to dose different amounts of calcium and alk is using brs 2 part?
 
magnesium will drop on it's own (slowly) it's a bit high but will not do any harm where it's at. test and dose what is needed. If the tank is using alkalinity, it is also using up calcium but not necessarily equally.
 
Ok, I just tested my mixed saltwater in my storage barrel and my readings are:
Mag - 1280
Cal - 420
Alk - 5.6 dKH

I have tested the alkalinity with 2 different kits and am getting the same results. I think I will order another brand of alkalinity test kit and see if there is something I am doing wrong with the Red Sea Pro kit.
 
The syringe with red sea kits is read opposite of how Salifert is read. It can be confusing.
Carefully go over the directions about how to read the syringe.
 
This is the first test kit that I have used in several years and though they are both red sea I've used 2 different kits to test it with the same results. They seem very straightforward and the amount of solution you use corresponds to the alk level. Each time it has only take like 4 or.5 to make the color change. I was fixing to order another kit from a different manufacturer to rule that out completely so I definitely don't want to over do it with the alk
 
how long has that salt water been sitting ? and at what temperature ? salt water can lose some alkalinity if it sits a long time, especially if it gets warm (precipitation). If it's freshly made and the alkalinity is that low, you have a bad batch of salt....
 
It has definitely been mixed for a while, a month at least and I do keep a small heater and power head in there. Maybe that's part of my issue. I'm dropping the alk unintentionally before doing water changes
 
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5.6?? That seems really weird, very whacky.
Yes, you're very correct - As I recall, the Red Sea pH/ALk kit has TWO columns to interpret your Alk. results, based on using 5ml of 10 ml of aquarium water.
I use the Salifert for this parameter. I feel it's more accurate and less confusing.

"It has definitely been mixed for a while, a month at least and I do keep a small heater and power head in there. Maybe that's part of my issue."

That's DEFINITELY at least PART of your issue, In my opinion. You're letting your prepped saltwater sit too long before using it.
Your pH was definitely on the low side as well.
You can also try using Sachem Reef Builder. It gently raises the carbonate alkalinity and if used correctly maintains or only SLIGHTLY raises the pH. Follow directions. Use the minimum dose recommended. It should bring your alkalinity slowly up.
The BICARB solution you're using might be also what's making your parameters so whacky. Use sodium carbonate (Reef Builders) instead. You'll need only HALF the amount to stabilize the alkalinity that you would with Sodium Bicarbonate. Trust me, it's more soulable and less a pain in the butt than what you're using.
 
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Thank you very the informative post. I may have misspoken about what I am using. I haven't been dosing anything and am just fixing to start which is what led me down this road. I have only added anything to my tank 2 times and that was the alkalinity portion of brs 2 part. I have my tank almost completely automated and for this to work properly I have to keep 30 to 50 gallons of saltwater premixed. Would taking the heater out and only running a powerhead in the barrel eliminate the alkalinity loss? The barrel is closed top but it does have 2 unsealed openings that I could close up tighter if that would help also. Again any advice is greatly appreciated
 
As far as the test kit I have 2 versions, one uses 2 columns and one only uses one column. With both I used 10ml of water so I used the .5dKH scale and I referenced how much titrant I used, not how much was left. I have done the test about 4 or 5 times now and i used like .38 the first time up to about.45 the last time after a couple does of the alkalinity portion of the brs 2 part. I have ordered a hannah tester for alk that should be delivered today before I make any more changes. Again thanks for all the replies
 
hanna works great ! you are going to like it......keep the stored water cold, it will help keep the alk from precipitating
 
Ok I added the heater to assist in mixing but see that it isn't needed. Will remove the heater and only leave the powerhead! Thanks!
 
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