Adding a pH probe to a Calcium Reactor

[melev]

Tim, thank you for providing us with some clear instructions for this project. Many DIY-ers will be happy to install one without fear.

Here's the article:
Do It Yourself – Adding a pH Probe Holder to a Calcium Reactor
http://reefkeeping.com/issues/2009-03/diy/index.php

[jimmyj7090]

FWIW if your cheap and impatient,

a 1/2" jon guest fitting from loews/HD will work for this project. You just need to carefully drill out the stopper lip inside the fitting. (carefully line it up in a drill press, drill with a 1/2" bit.

[not_sponsored]

Yep the 1/2" john guest fitting also fits into 1/2" NPT PVC so you can just add it at a joint.

[stugray]

And some safety suggestions:

If you are going to use a power tool to drive a tap, leave the chuck slightly loose. That way the chuck will slip before the tap breaks if it binds ( although with the size hole you are tapping that is very unlikely ).

It is also better to use a hand drill so you can reverse directions often.
Most drill presses dont have a reverse.

Stu

[jasoncw]

Drill press + tap = bad news unless you are experienced in this sort of thing. Unless the hole is too big, I always prefer to tap by hand. Much less risk of messing up the threads.

[One Dumm Hikk]

I am still looking for the "drill guide for NPT tap and drill sizes" as I don't see a link to one. Did it get left out?

[jasoncw]

Did you just by an individual tap? The container/sticker should state the drill bit size needed. Or, from http://www.korit.com/tapndrill.htm:

National Pipe Tapered Tap Chart
(Recommended tap drill to use for 75% depth of thread)

To Tap This Size Pipe:  Use This Drill Bit:  (Closest Fractional):  Decimal Inches: 
1/8-27 NPT              Ltr.R                -                       .3390 
1/4-18 NPT              7/16"                7/16"                   .4375 
3/8-18 NPT              37/64"               37/64"                  .5781 
1/2-14 NPT              45/64"               45/64"                  .7031 
3/4-14 NPT              59/64"               59/64"                  .9219 
1-11 1/2 NPT            1 5/32"              1 5/32"                1.1562 
1 1/4-11 1/2 NPT        1 1/2"               1 1/2"                 1.5000 
1 1/2-11 1/2 NPT        1 47/64"             1 47/64"               1.7344 
2-11 1/2 NPT            2 7/32"              2 7/32"                2.2188

[ksmith68114]

I love this add on. Does anyone have a good design for a DIY calcium reactor?

[melev]

There is a huge thread about a square one here on RC. I summed it up to one page on my site simply because it was such a long thread.

You know what? I think I can link this one, because it is doesn't go to my website and is merely hosting the actual information on this orphan page.

http://melevsreef.com/dj88.html

[scaryperson27]

cool info

[ksmith68114]

Thanks! Looks like a great design! I am going to try it.

[MplsMan]

ok so i'm wondering if it is better to read the ph from the reactor or from the efluient?
i have a probe in a seperate acrilic box with a hole to drip into the sump.
i've been deciding whether to drill a hole into the top of the reactor if i get a beyyer reading.

[hllywd]

Originally posted by jasoncw
Drill press + tap = bad news unless you are experienced in this sort of thing. Unless the hole is too big, I always prefer to tap by hand. Much less risk of messing up the threads.

I thought the same thing... I may use the idea by chucking the tap and rotating it by hand to start it square... my first go round by hand was off a little and it looks funny if your critical of those things... I have enough 6" tube to build 2 more. They'll be a little more polished than the first because of this article!

MplsMan ok so i'm wondering if it is better to read the ph from the reactor or from the efluient?

The reading inside should be a little more accurate.

Tim

[melev]

Originally posted by MplsMan
ok so i'm wondering if it is better to read the ph from the reactor or from the efluient?
i have a probe in a seperate acrilic box with a hole to drip into the sump.
i've been deciding whether to drill a hole into the top of the reactor if i get a beyyer reading.

I ran my reactor for years with a beer cup and later an acrylic effluent box. It works very well, provided the effluent continues to drip or pour. If you check it daily and make sure it is flowing like it should, it works fine.

However, if the effluent ceases to exit, the pH probe in the cup is NOT measuring the fluid in the reactor because nothing new is coming out. So while the effluent liquid sitting in your cup is at a certain level (and thus controlling the CO2's solenoid), the pH in the reactor could be dropping. This happened to me twice. The stagnant effluent measured at a level where it signaled the reactor needed more CO2, when in fact there was much too much already, and the media turned to mush.

It isn't a big deal in that it won't hurt your tank, but you end up with wasted media that you have to remove and replace. The probe in the reactor should help avoid that.

[2dawghouse]

Originally posted by MplsMan
ok so i'm wondering if it is better to read the ph from the reactor or from the efluient?
i have a probe in a seperate acrilic box with a hole to drip into the sump.
i've been deciding whether to drill a hole into the top of the reactor if i get a beyyer reading.

That is what I have been wondering as well for my dual chamber DIY reactor. I figured measuring effluent within the first stage of the reactor is the way to go.

[MplsMan]

Originally posted by melev
I ran my reactor for years with a beer cup and later an acrylic effluent box. It works very well, provided the effluent continues to drip or pour. If you check it daily and make sure it is flowing like it should, it works fine.

However, if the effluent ceases to exit, the pH probe in the cup is NOT measuring the fluid in the reactor because nothing new is coming out. So while the effluent liquid sitting in your cup is at a certain level (and thus controlling the CO2's solenoid), the pH in the reactor could be dropping. This happened to me twice. The stagnant effluent measured at a level where it signaled the reactor needed more CO2, when in fact there was much too much already, and the media turned to mush.

It isn't a big deal in that it won't hurt your tank, but you end up with wasted media that you have to remove and replace. The probe in the reactor should help avoid that.

very interesting!
so if i consider doing that what do you want the ph in the reactor at, i have mine at the efluient at 6.5
would it be lower or higher.

[melev]

You would want it at 6.5, MplsMan.

[MplsMan]

ok thanks very much.

[2dawghouse]

Does the effluent pH rise alittle after some media has been dissolved within the reactor?

[melev]

The effluent will vary, based upon the CO2 going into the reactor. If the CO2 shuts off (or bubbles too slowly), the tank water feeding into the reactor at 8.3 will definitely dilute the pH level within the reactor. Thus the pH in the reactor and in the effluent coming out will go up.

The pH controller would measure either source, and when it hit a specific amount (usually around 6.9), it would turn the CO2 back on or the hobbyist would need to increase the bubble rate on the regulator's bubble counter.

My own solenoid broke a few months ago, so I have mine dialed in to where the pH in the reactor is between 6.4 and 6.5 daily. By opening and closing the pinch clamp on the effluent tubing, I can dial it in if necessary. Closing the line to slow down the output will lower the pH in the reactor, and opening the line will raise the pH because more tank water is passing through it at a quicker rate.

[CleveYank]

Hand tapping only.
Power tapping is too risky not to mention the "work" can get jammed up on the tap and break loose. Some drill presses have alot of torque and torque can equal injuries if scenarios unfold just right.

[sailfintang]

Great Thjread subscription added, this will be great for my DIY reactor. thank a bunch

[luisgo]

I installed my PH probe in my reactor the same way as explained in this post. It works very nice. There are some photos in the following link. It is in spanish but the photos will tell how it was done.

http://www.createforum.com/phpbb/vie...5&mforum=amepr