DROP CHECK setup - alternative process

[finz]

Folks,

I start out with RO/DI water that has a hardness of .03 dH - assuming my PINPOINT Conductivity Monitor is working correctly - and I belive so as I calibrated the unit prior to starting.

So, 4dh equates to 132µS and using KENT RO/RIGHT brought my base RO/DI water to the desired spec - I believe.

Regards RO/RIGHT, right on the labeling it recommends electronic testing to measure hardness but I'm aware that it not give the origin of the ions, whether they are Mg, Ca, or Fe. However, starting with essentially 'pure' water and adding what I hope is the 'right' mix of minerals, I believe I'm good to go. Your feedback is appreciated here.

Next I added the supplied reagent which interestingly starts out in a seemingly emerald green state and even when combined with my treated water , still appears emerald green (didn't expect a color change here but to point out that even in a diluted form, it's still green!).

Point is for me, 'green' is to suggest optimal CO2 and if my base case IS green, am assuming the reagant is bad.

Appreciate your feeback.

 

[phanmc]

The reagent (bromothymol blue) may be green in it's pure form which shows that the solution itself is neutral (7pH). However, when adding it to the treated distilled water the solution should be blue.

Try using regular baking soda instead of Kent's product to raise the kH.

 

[finz]

Thanks PHANMC - you are right on the money!

I can't express how absolutely fun this exercise has been both from a technical and educational perspective.

I literally felt like a chemist mixing this and mixing that while using my electronic testor to measure m results.

Also, the difference between Carbonic hardness and General Hardness became more clear and for me brought about a startling and observable fact that, in terms of overall hardness and measuring electronically, one 'type' of hardness drops pH while the other , although not raising it, makes pH harder to drop!

One thing too that disappointed me was that I expected my RO/DI water to be a tad 'cleaner' especially since where I wanted to go up the 'hardness' scale was so close to absolute Zero. Am assuming I need to inspect my system a tad closer to make sure all stages of the filtration process are in check.

My next stop is to the grocery store to purchase a few gallons of Distilled water (from various vendors) and test base conductivity between them and of course the water I now produce.

Finally, I highly recommend this exercise to the masses as it, as I've already stated, is both fun and educational :grinyes: !!

 

[The Zigman]

I just gave up and ordered the 4dKh soultion...
I got it in 2 days from Florida...

http://www.greenleafaquariums.com/co2-drop-checkers.html


BTW if your water is that soft, it should turn blue on the first drop...

My tap water is so hard I need like 6 drops to get it blue..
the 4dkh 1 drop was blue, 2 drops was really blue..

 

[jmhart]

As you have already become aware, Kent's RO Right is a GH booster, not a KH booster. As mentioned, try a carbonate source like sodium or calcium carbonate.

Great experiment though, best way to learn is to get right in there and do it.

 

[finz]

BTW if your water is that soft, it should turn blue on the first drop...

I'm very confident that my water is very soft (as per my Kent Marine Maxxima R.O./D.I Hi-S 60 GPD).

Just recently swapped out the Resin unit (DI) and further back swapped out the RO unit so assume I need to had a look at my segement and carbon filter - they generally require changing quite frequently and I imagine I slipped here somewhere.

Also, as I'm not running saltwater, I've been not too concerned about metal parts inline from the filter to my sump - normally wouldn't even bother here but since I'm now a chemist :grinno:, will need to consider the earlier decision.

But really .04 dH is still quite soft and once I work my filters expect to get back down to .01 ...

Finally, I understand that two types of reagants are used on this process... Bromothymol blue which I'm using isn't an 'add more drops till it getz blue' sorta deal... But perhaps what you are using is.

 

[Squawkbert]

One thing too that disappointed me was that I expected my RO/DI water to be a tad 'cleaner' especially since where I wanted to go up the 'hardness' scale was so close to absolute Zero.

RO/DI units that produce water with a resistivity in excess of 10Mohm*CM are a tad pricier than what is commonly seen in the trade. For example, a Millipore Gradient A10 unit, if well fed, can produce >18Mohm*CM water with UV breakdown of total organic carbon to the single digit PPM range at a rate of ~1L per minute - for about $10,500. Annual upkeep for a moderately used unit involves swapping out of one or two (different) UV lamps and several filter cartridges, none of which are cheap (figure on annual spending of at least 15-20% of your original outlay to keep it going).

If your unit is delivering water with even 1Mohm*CM of resistivity, you're most of the way there at a small fraction of the cost we in the lab pay for product water.