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nrannalli
10/19/2009, 03:14 PM
I have too different test kits one is a Red Sea ph and alk test and the other is a Seachem mg and alk test. Does anyone know what the Red Sea kit is testing for? Borate? Carbonate? or Total Alk? I emailed them and like most companies no a days no response so I was hoping some one here might know.

The reason I am ask is because my Seachem test is reading 4.8 meq total alk (2.8 borate and 2.0 carb) but the red sea will only read 2.0 meq (?) not matter how much baking soda I add. I tried baked baking soda, baking soda right out of the box and mixtures of both. The first raises the ph very rapidly the second lowers it rapidly the mixture gives me a more balanced buffer. But I am ready to throw this Red Sea kit away because it is not doing me any good not knowing what it is measuring.

Thanks
Nick

Randy Holmes-Farley
10/19/2009, 03:29 PM
What salt mix? Ever add Seachem Marine Buffer?

All alkalinity kits test for total alkalinity unless you do a special Seachem test and measure borate alkalinity (a flawed test last I tested it) and then subtract that value from total alkalinity to get bicarbonate/carbonate alkalinity. :)

The 2.8 meq/L borate alkalinity test result is likely not accurate, unless you've manually added a ton of borate to the water. It usually reads too high:

The Seachem Borate Alkalinity Test Kit
http://www.advancedaquarist.com/issues/june2003/chem.htm

Of course, that does not imply the the Red Sea is accurate either. :D

nrannalli
10/19/2009, 03:50 PM
I use the Coralife salt it seems to work best in my tank. I haven't added any manufactured buffers in over a year. All I use in the tank is a mixture of baked and none baked baking soda and Mrs. Wages and it seems to work very well. I also use a CA reactor with ARM and Dolomite ph 6.5-6.9. Even with the reactor and kalk it can not keep the Alk above 2 meq I add about .5meq a day to keep it a 2.5-3 meq. The tank also consumes about 20 gallons of saturated kalk in 5 days.

S - 1.026 (Refrac)
CA - 520 ppm (Seachem)
MG - 1750 (Seachem)
Borate - 2.8 meq/L (Seachem)
Carb - 2.0 meq/L
TAlk - 4.8 meq/L
PH - 7.9-8.2 (RKL Probe and Red Sea Kit) .

I did use BRS sugar sized CaCl2 and MgCl2 with Mg3(PO4)2 a couple of weeks ago. So I wasn't total honest about the not using any manufactured buffers in the last year.

Randy Holmes-Farley
10/19/2009, 03:51 PM
I use the Coralife salt it seems to work best in my tank.

Just ignore the borate part of the Seachem kit them. The total alkalinity part was accurate when I tested it. :)

Billybeau1
10/19/2009, 09:14 PM
I would throw the Red Sea kit in the trash. And the Seachem for that matter.

Pick yourself up an inexpensive API kh kit or a Salifert or Elos if you want finer numbers.

Like Randy said, focus on total alkalinity. That's all you need to worry about.

You might as well throw the Seachem magnesium kit out as well. I doubt your mag level is 1750 ppm unless you have been dosing heavy amounts of mag supps. :)

wayne in norway
10/20/2009, 06:37 AM
But all of those numbers for Ca, Mg and Total alk are high, though it's hard to know what the 'real' alk is from the Total as the borate reading is so unreliable.

Perhaps it's worth backing off some of the supplements?

bertoni
10/20/2009, 12:44 PM
I might back off the supplements. If any animals seem to be having trouble, some large (20% or so) water changes might help. I had very bad experiences with my Red Sea test kits, which seems to be a common complaint.

nrannalli
10/21/2009, 04:30 PM
Billybeau1 - Using the ref mg from the test kit it is within range so I am pretty sure the test is right. I also added around 12lbs of a MgCl2 and Mg3(PO4)2 mixture over 15+ days to bring the level up. So I don't think I will be trowing it away at this point. I will also look at trying one of the API kits as for Salifert have never had any luck with their test and besides they are way over priced.

I keep the MG high for my ManGroves and I am fighting off some Bryopsis at the moment. I am fine with the numbers for Calcium and Alk but I am not fine with the results from the Red Sea kit. If I keep my dosing at a rate to make the Red Sea kit read around 3.5-4 meq/L where I want it it is in the high 5-6 meq/L on the Seachem kit and the tips of my sps burn. So I will just stick with the Seachem kit because it has worked fine for me in the past. But my kit is running out of Alk test and I didn't want to have to buy the whole MG and ALK test kit. I like to keep my levels where they are at because my SPS grow like crazy, my zoos spawn and my fish and shrimps seem to be happy. I also never have to clean calcium deposits off of my equipment.

arredondojason
10/21/2009, 05:51 PM
[QUOTE=Randy Holmes-Farley;15882718]Ever add Seachem Marine Buffer?

ok i have seen this in alot of forums but no reason behind it i am just wondering why everyone asks this.
thanks.

Billybeau1
10/21/2009, 06:30 PM
Billybeau1 - Using the ref mg from the test kit it is within range so I am pretty sure the test is right. I also added around 12lbs of a MgCl2 and Mg3(PO4)2 mixture over 15+ days to bring the level up. So I don't think I will be trowing it away at this point. I will also look at trying one of the API kits as for Salifert have never had any luck with their test and besides they are way over priced.

I keep the MG high for my ManGroves and I am fighting off some Bryopsis at the moment. I am fine with the numbers for Calcium and Alk but I am not fine with the results from the Red Sea kit. If I keep my dosing at a rate to make the Red Sea kit read around 3.5-4 meq/L where I want it it is in the high 5-6 meq/L on the Seachem kit and the tips of my sps burn. So I will just stick with the Seachem kit because it has worked fine for me in the past. But my kit is running out of Alk test and I didn't want to have to buy the whole MG and ALK test kit. I like to keep my levels where they are at because my SPS grow like crazy, my zoos spawn and my fish and shrimps seem to be happy. I also never have to clean calcium deposits off of my equipment.

Reference solutions are garbage IMO. They do not prove a thing. I once had a Seachem calcium kit and the reference solution matched the kit perfectly. However, the calcium reading from that kit was 70 ppm lower than 5 other kits I tested it against. Reference solutions are just a gimmick IMO and does not tell the true tale of a test kits accuracy.

Billybeau1
10/21/2009, 06:34 PM
[QUOTE=Randy Holmes-Farley;15882718]Ever add Seachem Marine Buffer?

ok i have seen this in alot of forums but no reason behind it i am just wondering why everyone asks this.
thanks.

That is because the pH lift you get from Marine buffer is short lived at best and all it does over time is increase alkalinity. Some reefers use this product to try and keep their pH in check and they just end up with very high alkalinity. Not recommended IMO.

nrannalli
10/21/2009, 07:11 PM
I think in this particular instance it has to do with the fact they use Borate salts to help stabilize the PH possibly causing my high borate readings. But if overdosed it can raise alkalinity to unsafe levels.

Billybeau1
10/21/2009, 09:18 PM
I'm not sure how you know your borate levels are high. I haven't seen a hobby grade test kit that can accurately measure borate yet. :(

bertoni
10/21/2009, 11:13 PM
Marine Buffer adds a lot of borate buffering to the mix, which isn't consumed by corals, and thus can "displace" carbonate alkalinity, which is more useful in a reef setting. Marine Buffer is fine for fish-only tanks, which is its intended use.

Randy Holmes-Farley
10/22/2009, 04:53 AM
Yes, that was my reason for asking. If there was a lot of use of Marine Buffer, borate alkalinity could be quite high.