Question 1

What is the source of the calcium used in your filter?  Is it calcite or something else?

Accepted Answer

This is the answer I received from Waterdrop to a similar question: 
Our MNR filter includes 18 kinds of natural mineral stone materials:
 
Subsurface rocks like Serpentine, sea pumice, Anorthite, Zinc Spinel, Bioclastic limestone, Baimo Dolomite, Magnetite, Wollastonite, Clinoptilolite, Volcanic Stone
 
Shallow underground rock:  like Kunlun Hetian Complex Rock, Marl, Clinoptilolite, Kaolin Ore, Tourmaline
 
Deep underground rock:  like Tianshan Maifan Stone, Potassium Feldspar, Basalt

The above combination of stone materials is a scientific formula to simulate the environment of the best natural spring water that benefits human health.
 
Please allow me to explain that our MNR filter includes 18 kinds of natural mineral stone materials:
 
a.  Subsurface rock like Serpentine, sea pumice, Anorthite, Zinc Spinel, Bioclastic limestone, Baimo Dolomite, Magnetite, Wollastonite, Clinoptilolite, Volcanic Stone
 
b.  Shallow underground rock:  like Kunlun Hetian Complex Rock, Marl, Clinoptilolite, Kaolin Ore, Tourmaline
 
c.  Deep underground rock:  like Tianshan Maifan Stone, Potassium Feldspar, Basalt

The above combination of stone materials is a scientific formula to simulate the environment of the best natural spring water that benefits human health.

Question 2

How much will this raise the ph level? At .50gpm(waterprop to system)

Accepted Answer

They sell an Alkaline filter, that will raise ph more, not this one.. 
All these other answers are wrong, talking about tds. Tds is total dissolved solids,  that is not Physical hardness(ph) tds measures minerals in water. Ph measures the acid level in water. 2 totally different things. This filter is for adding minerals back not really raising ph so you can have Alkaline water.

Question 3

Has anyone cut this open after use to see what remains?  i couldn't tell by taste if anything is even happening.  time to buy a tds tester.

Accepted Answer

TDS testers are a must have and are cheap.

Question 4

How do you know that this isnt just adding arsenic and heavy metals back into the water?

Accepted Answer

Hi,
Thanks for your interest in our MNR filter product.

Please rest assured that only beneficial mineral will be added into the filtered water, and we use natural mineral rocks as source, so there will be no heavy metal releasing into the water, thank you.

If you have contacted us via email but received no reply, please check the Spam/Junk Folder first. Thank you.

If you have any other inquiries, please feel free to contact us.
1-888-352-3558

Kind Regards
Mia Lauren　
Customer Service Rep

ASIN	B08DXYL81C
Best Sellers Rank	#4,111 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #8 in Under-Sink & Countertop Filtration
Brand	Waterdrop
Brand Name	Waterdrop
Customer Reviews	4.5 out of 5 stars 1,813 Reviews
EU Spare Part Availability Duration	9 months
External Testing Certification	RoHS
Included Components	MNR35 Remineralization Filter * 1, User Manual
Item Dimensions D x W x H	2.6"D x 2.6"W x 11"H
Item Weight	12.64 ounces
Manufacturer	Waterdrop
Manufacturer Part Number	WD-MNR35
Manufacturer Warranty Description	1 year manufacturer and Seller Combination
Material	pp cotton
Material Type	pp cotton
Model Number	WD-MNR35
Number of Items	1
Product Benefits	Restore Essential Minerals
Product Dimensions	2.6"D x 2.6"W x 11"H
Set Name	WD-MNR35
Unit Count	1 Count

Waterdrop MNR35 Remineralization Filter Compatible with Undersink RO System | 1/4" & 3/8" Quick Connect Filter for RO Water Filter, Restore Essential Minerals, 9-12 Month Lifetime, 1-Pack

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