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boobookitty
12/16/2016, 12:02 PM
I run an Apex system on my 400G, and I've had the pH probe in the sump since the beginning; pH there runs between 8.0 and 8.2 pretty consistently, despite having a Dastaco CA reactor that drips into the sump. But it occurred to me that the tank might be different, and I moved the pH probe (along with temp and salinity probes) into the main tank (and recalibrated it).

I've found that the main tank runs pretty low, generally between 7.70 and 7.90. That seems too low to me, although I guess it's been that way for a while. The tank does ok, but I do have periodic issues that I'm wondering might be related to chronic low pH.

Should I worry about this? Take steps to try to raise the tank pH?

klwheat
12/16/2016, 12:45 PM
what are your other levels in the tank? alk? What are you dosing?
Also, just a thought because I had this issue, how "closed" is your house? In my house with 4 people and 4 large dogs, and tight insulation, I just had too much CO2 inside. Opening the windows made a huge difference. The other thing I did (can't open the windows all year here in TX...lol) was put CO2 absorber on my skimmer intake. Now I hover between 8.2-8.35 instead of 7.8-7.95.

Optionman
12/16/2016, 12:58 PM
can i please get some info on the CO2 absorber you added to your skimmer? my PH, as detected by apex probe near down flow pipes in sump, ranges between 7.9-8.10 during the day. My CA reactor drips into a different area of the sump at a PH of approx 6.5.

thanks in advance

boobookitty
12/16/2016, 01:18 PM
Alk is 8.5, CA is 440, Mg is around 1300; those are fairly stable. Temp ranges from 79.0 to 80.0

And yes, interested in the CO2 absorber for the CA reactor. Would that be on the drip back into the tank.sump?

klwheat
12/16/2016, 01:18 PM
This is basically what I've been using.
http://www.bulkreefsupply.com/brs-color-changing-medical-grade-co2-absorbent.html
(if I'm not allowed to post link, please remove)

klwheat
12/16/2016, 01:19 PM
Alk is 8.5, CA is 440, Mg is around 1300; those are fairly stable. Temp ranges from 79.0 to 80.0

And yes, interested in the CO2 absorber for the CA reactor. Would that be on the drip back into the tank.sump?

Your parameters seem pretty much the same as mine (a little warmer). This is CO2 absorber for air. It removes excess CO2 that is introduced through skimmer and such.

boobookitty
12/16/2016, 01:21 PM
Do you use it in a reactor? How do you plumb it to skimmer?

klwheat
12/16/2016, 05:53 PM
I'll see if I can post a pic when I get home for ya.


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homer1475
12/16/2016, 06:04 PM
Your PH is absolutely fine at 7.70, if it dipped any lower I might be concerned. But I would start with something simple first like adding an outside airline to my skimmer, or a CO scrubber on the intake line to the skimmer, before I did anything drastic.

What I find odd is that you reported that your sump PH is higher even though your running the effluent from the CA reactor into the sump. Typically where you dump the reactor in has a low PH as the PH coming from the reactor is more like 6.0(has to be low to dissolve the media).

klwheat
12/16/2016, 06:05 PM
Here's a YouTube video that should give you the basic idea (it's not mine, but same idea). If the YouTube link isn't ok, please remove mods.
https://m.youtube.com/watch?v=LSC1J0PRIs0


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boobookitty
12/16/2016, 06:38 PM
@klwheat: Interesting...so you pull fresh air from a distance as well as filtering it through the adsorbant? i like the use of the RO/Di canister...I have a couple of those lying around. :)

@homer1475: Yah, I was surprised as well. I thought the sump would have a lower reading...

klwheat
12/16/2016, 06:43 PM
I don't pull air from further away, I just have the intake from my skimmer hooked to the canister


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boobookitty
12/16/2016, 06:54 PM
Got it, thanks. I'm going to give it a try...

klwheat
12/16/2016, 06:55 PM
Sweet. Let us know how it works!


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klwheat
12/17/2016, 01:00 PM
Also, if possible while you're waiting to get it set up, try opening several windows near the tank and see if that makes a difference. That should give you some Indication as to whether or not elevated CO2 is your problem.


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jonwright
12/17/2016, 08:52 PM
Take a sample of water. Test ph of that sample, record. Take sample outside and aerate it for a while. 30 min will do. Record ph. If significantly higher your house has too much co2.

I left a window open for a day or two and that fixed my ph issues. I tried a co2 absorbant hooked to my skimmer air intake. Was very drastic, quick, and ballooned up and down depending on how spent it was.

I wound up just leaving the windo cracked. Much more stable AND my dehumidifier didn't run all the time.

klwheat
12/18/2016, 12:18 AM
I'd leave my windows open too...but not an option year round here in TX...lol


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boobookitty
12/22/2016, 12:25 PM
Update: I plumbed in CO2 adsorber and it raised pH to 8.0-8.2, which is what I wanted. The amount of adsorber I'd need if this were permanent concerns me, so now that I know it's CO2-related in that room, this morning I plumbed the skimmer air intake to an outside feed. I'll see if the pH stays up enough with that.

bertoni
12/22/2016, 02:04 PM
Okay, that sounds like a reasonable approach. The skimmer approach works for some people. I hope it helps with your tank.

klwheat
12/22/2016, 04:09 PM
Good to hear. Depending on the air draw of the skimmer, and how "bulk" you get the absorbent, it can definitely get expensive. The outside intake is definitely a good idea, just wasn't an option for me.


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boobookitty
12/23/2016, 01:08 PM
Update: After removing the CO2 adsorber and plumbing tubing onto the skimmer air intake, the skimmer air tubing just went under the house, and the pH went back to almost what it used to be, ranging from 7.85-8.03. That's a little better than the original range (7.8-8.0) but not as good as with the adsorber (8.0-8.2).

So this morning I extended the tubing to outside in the back yard. I'll see how it affects pH today.

boobookitty
12/24/2016, 10:30 AM
Plumbing the air intake to the backyard didn't help the pH at all. So to summarize:

- Tank pH running 7.8-8.0 using room air

- Plumbing air intake to under house raises it a little to 7.85-8.03

- Plumbing it all the way to backyard doesn't improve on that

- CO2 adsorber on the air intake raises tank pH to 8.0-8.2


So am I just stuck with using adsorber to keep pH high? I thought the plumbing to the back yard would be like using adsorber; apparently there's too much CO2 out there too?

Orr2003
12/24/2016, 11:25 AM
I am also going to be using a CO2 absorber on the air intake of my alpha 250 once all is set up. But what I am going to do is run the intake to the CO2 media filter to the outside in hopes to extend the life of the media and save some $.

I have never used this method but have had many tanks that ran on the low end of PH range.....so my question is....I know it depends on how much CO2 is entering the media but on average how often do you need to change the CO2 absorber? BRS site says you get 7 refills out of a 9lb jug. Just curious about how long this might last? 2 months?

boobookitty
12/24/2016, 11:36 AM
That's the question, and it depends entirely on how much CO2 it's pulling out. I've heard as bad as every couple days, all the way up to a couple weeks. I guess I'll find out. :)

Orr2003
12/24/2016, 12:05 PM
That's the question, and it depends entirely on how much CO2 it's pulling out. I've heard as bad as every couple days, all the way up to a couple weeks. I guess I'll find out. :)

Keep us updated. Are you going to run the intake to the CO2 filter to under the house? Curious to know the difference in depletion rate from intake inside to outside.

boobookitty
12/24/2016, 12:14 PM
Yah, I'll leave the run out to the backyard, although I won't be able to compare since I only ran the adsorber for a day or so.

boobookitty
12/29/2016, 12:12 PM
Definitely perplexed. Piping in fresh air from the backyard as opposed to using air from under the tank seems to make no difference; tank pH stays about the same. But running either through a CO2 absorber raises tank pH to where I want it. Could my outside air have the same high levels of CO2 as the stale air under the tank?

jason2459
12/29/2016, 12:54 PM
Plumbing the air intake to the backyard didn't help the pH at all. So to summarize:

- Tank pH running 7.8-8.0 using room air

- Plumbing air intake to under house raises it a little to 7.85-8.03

- Plumbing it all the way to backyard doesn't improve on that

- CO2 adsorber on the air intake raises tank pH to 8.0-8.2


So am I just stuck with using adsorber to keep pH high? I thought the plumbing to the back yard would be like using adsorber; apparently there's too much CO2 out there too?
All of those ranges are acceptable so I wouldn't say you are stuck using the CO2 scrubber.

I personally like to have pH above 7.9 but it's not necessary.

I can give you my experience and some may help you.

My pH with out any intervention drops under 7.8 and even 7.7 especially in the winter with fires and furnace going.

With limewater(kalk) dosing done via ATO my pH stays above 7.8 (usually...)

With lime dosing done separate from ATO and done constantly 24/7 (mine runes for 1 second every couple minutes) my pH stays above 7.9

With my ATS running or macro algae running opposite display light schedule or longer bumps my pH a couple tenths

Adding a CO2 scrubber with all that keeps my pH above 8.0

bertoni
12/29/2016, 08:11 PM
The problem might be the rate of air flow from outside. The carbon dioxide scrubber probably is going to drop the level a lot. The outside air will be much closer to the inside air content in terms of carbon dioxide. You might need to increase the flow significantly.

jonwright
12/31/2016, 02:59 PM
Definitely perplexed. Piping in fresh air from the backyard as opposed to using air from under the tank seems to make no difference; tank pH stays about the same. But running either through a CO2 absorber raises tank pH to where I want it. Could my outside air have the same high levels of CO2 as the stale air under the tank?

Well something to consider is the length of tubing and diameter. Generally for longer runs you'd presumably need larger diameter tubing. Did you do that? Did you have to readjust your skimmer to use the longer run to the back yard?

The longer run MAY be pulling a smaller volume of air to the tank.

It could be that there isn't as much of a difference outside than there is inside to warrant such a large swing vs. the adsorbent. Wasn't clear to me via the posts how long you ran each setup.

I run the adsorbent occasionally for mine. Otherwise I'd be going through a new gallon just every month. Not a killer in and of itself, but a lot of stuff like that just adds up after a while. I keep the window cracked but when it got really cold I closed it, then we had a bunch of folks hanging out in the house due to the holidays, so I"m running the absorbent now. Will take it back off after a day or so.

boobookitty
12/31/2016, 06:06 PM
Air flow is definitely a little less when plumbed from the outside. Originally the run to the skimmer air intake is through 5/16" tubing, about 1 foot to a standpipe that's 3/4" diameter. In the new configuration, the 5/16" tubing goes to the CO2 absorber, then about 5 feet of 1/2" pipe to under the house, which expands to about 5 feet of 3/4" pipe. Suggestions on how to increase airflow close to original would be appreciated...bigger pipe needed?

bertoni
12/31/2016, 06:13 PM
You could try a larger diameter line, or look into an air pump. I don't know whether a larger diameter line will do enough, but if it's easy to try, it's worth a shot, in my opinion.

jonwright
01/01/2017, 08:23 AM
I know with messing with HVAC stuff there are calculators on size of ducts needed for CFM draw/push depending on length of run. Now, translating that to the small amount of air needed for a skimmer wouldn't be rather straightforward unless we have someone monitoring this thread that knows what CFM your skimmer needs and help calculate it.

If you wanted to science the sh!t out of it you could get a small CFM meter that some folks use to dial in their skimmers. Personally I wouldn't do that. I'd think if you could get away with a 1" pvc pipe run to begin with that may be enough (be sure to limit the turns/elbows etc as much as you can). Then at the last possible inch convert to size needed for your skimmer. And no, I wouldn't particularly worry with glue on the PVC unless it's needed for holding it together.

Basically you'd want the end result of running your outside line to have minimal effect on your skimmer set up - that would mean that your air draw is comparable.

But if you could use what you have and start with keeping the 3/4" run that would let you know if you are going in the right direction methinks - unless that's just as complicated as doing a 1" run anyway.

boobookitty
01/01/2017, 11:20 AM
Realized that I was forcing the air through 1/4" because I'm using an RODI canister. So I've widened that to see if it makes a difference.

On a separate note, anyone know if new absorber that accidentally got wet can be dried, or is it shot?

bertoni
01/01/2017, 05:55 PM
The absorbent might be usable after drying, but it will have reacted with some carbon dioxide in the water and more with the air as it dries, so it might not last long. It should be fine to give it a try, though.