Changing Water Changing Parameters

Darth_Tater · 04/23/2017, 03:07 PM

So I made a rookie mistake last week and messed up a Magnesium test. It read very low, and instead of double checking I dosed some Mag. This ended up putting my Mag level off the charts (literally, all I know is it was above 1600).

After realizing my mistake, I decided to do a series of 10 gallon water changes every day until the Mag dropped to where I want it (about 70 gallons in the system). After 2 days of this I realized the new water I was adding was throwing off my other 2 parameters as well since the newly mixed saltwater has a much higher Alk level than I want. This was causing stress to my SPS.

I've decided now that the best course will be to just leave the Mag dosing pump off and reduce the Alk dosing amount and let things slowly settle and track the parameters every couple days until they drop to where I want them.

If anyone has other recommendations I'd appreciate them. I'd also like some ideas on how to do large water changes without throwing all the parameters out of whack for future reference. Is it best to keep the parameters close to the newly mixed saltwater? Or am I missing something? Thanks!

Vorog · 04/23/2017, 03:21 PM

It sounds like you did the best thing. I too have had this happen and just let things slowly work itself back to stabilizing. I have done two large water changes on my system (90 gallons of actual water volume) I try to measure everything on the tank as well as the new water to make sure they are the same temp, ph , salinity, cal,all,mag etc. it seems not matter how careful you are the system will still be somewhat shocked. So I like smaller more frequent water changes.

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billdogg · 04/23/2017, 04:59 PM

Just leave it all be. The magnesium will drop slowly over time. FWIW - I don't use a dosing pump for Mg - When I test and it's low, I just pour in however much the BRS calculator says it needs.

Ron Reefman · 04/23/2017, 05:24 PM

+1 to what others have said.

For what it's worth, I ran Mg levels up to 2200 trying to kill off an algae. It did no harm.

Darth_Tater · 04/23/2017, 05:34 PM

Ok, thanks for the sanity check everyone!

Quote:

Originally Posted by billdogg

FWIW - I don't use a dosing pump for Mg - When I test and it's low, I just pour in however much the BRS calculator says it needs.

I have a 3 pump doser so I am dosing the Mag so I don't feel like I wasted money. It's a very small amount, something like 5 mL a day (vs. the 150-ish mL a day of the other 2).

04/23/2017, 03:07 PM	#1
Darth_Tater Registered Member Join Date: Feb 2015 Location: Northern Utah Posts: 535	Changing Water Changing Parameters So I made a rookie mistake last week and messed up a Magnesium test. It read very low, and instead of double checking I dosed some Mag. This ended up putting my Mag level off the charts (literally, all I know is it was above 1600). After realizing my mistake, I decided to do a series of 10 gallon water changes every day until the Mag dropped to where I want it (about 70 gallons in the system). After 2 days of this I realized the new water I was adding was throwing off my other 2 parameters as well since the newly mixed saltwater has a much higher Alk level than I want. This was causing stress to my SPS. I've decided now that the best course will be to just leave the Mag dosing pump off and reduce the Alk dosing amount and let things slowly settle and track the parameters every couple days until they drop to where I want them. If anyone has other recommendations I'd appreciate them. I'd also like some ideas on how to do large water changes without throwing all the parameters out of whack for future reference. Is it best to keep the parameters close to the newly mixed saltwater? Or am I missing something? Thanks! __________________ It's probably in your best interest to ignore most of my advice.

04/23/2017, 04:59 PM	#3
billdogg Registered Member Join Date: Apr 2008 Location: Grove City, Ohio Posts: 10,806	Just leave it all be. The magnesium will drop slowly over time. FWIW - I don't use a dosing pump for Mg - When I test and it's low, I just pour in however much the BRS calculator says it needs. __________________ I'll try to be nice if you try to be smarter! I can't help that I grow older, but you can't make me grow up! Current Tank Info: 120 mixed reef with 40b sump, RO 150 skimmer, AI Sol Blue x 2, and a 60g Frag Tank with 100g rubbermaid sump. 2 x Kessil A360w lights, BM curve 5 skimmer

04/23/2017, 05:24 PM	#4
Ron Reefman Registered Member Join Date: Jul 2009 Location: Cape Coral, FL Posts: 10,431	+1 to what others have said. For what it's worth, I ran Mg levels up to 2200 trying to kill off an algae. It did no harm. __________________ The good thing about science is that it's true whether or not you believe in it. (Neil deGrasse Tyson) Visit my build thread http://www.reefcentral.com/forums/showthread.php?t=2593017

04/23/2017, 03:21 PM	#2
Vorog Registered Member Join Date: Jan 2014 Location: Tampa, FL Posts: 413	It sounds like you did the best thing. I too have had this happen and just let things slowly work itself back to stabilizing. I have done two large water changes on my system (90 gallons of actual water volume) I try to measure everything on the tank as well as the new water to make sure they are the same temp, ph , salinity, cal,all,mag etc. it seems not matter how careful you are the system will still be somewhat shocked. So I like smaller more frequent water changes. Sent from my iPhone using Tapatalk