CO2 on/off and pH fluctuations

Dmaaaaax

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I have been setting up a planted tank to house Discus. I know that most people have their CO2 on a timer with their lights and was curious how much their pH fluctuates first thing in the morining when the CO2 was off (should be high) to when the lights are just about to turn off at night (should be low). Is this fluctuation ok for fish like Discus that seem to stress over pH changes?

I currently am running my CO2 with a solenoid connected to pH controller. I have the pH adjusted so that when my CO2 dropchecker appears a yellow green it will turn off/on to keep close to that color. I am using 4kH distilled water in my dropchecker. My biggest fear with my current setup is that O2 will be low during the night when the plants start to take it in since CO2 is constantly being injected/controlled by pH.

Are there any Discus owners out there with some tips. Other forums don't seem to have any Discus owners with injected CO2 setups.
 

The Rockster

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This applies to Domestic Discus ONLY

Dmaaaaax;32882 said:
I have been setting up a planted tank to house Discus. I know that most people have their CO2 on a timer with their lights and was curious how much their pH fluctuates first thing in the morining when the CO2 was off (should be high) to when the lights are just about to turn off at night (should be low). Is this fluctuation ok for fish like Discus that seem to stress over pH changes?

I have had Discus for a few years. They seem to be very tolerable with the CO2. I have an automated system with controller. The CO2 turns off with the lights. Although, truthfully, I have never pushed the CO2, anywhere close to gassing them out. I too have a d/c with 4 degree water. I keep it on green.
I also personally believe (with no proof), that fish can stress, to a lesser degree,with out showing the obvious, extreme signs, and will have a decreased life span. This is true in other species.......ie......parrots and people.:(
The fish are like family here, semi trained to come to the one feeding them, complete with names, my grand kids really enjoy them to whit: the plants are secondary. (in preference and cost) :eek:

Lately, I have been running air bubbles at night.(Thanks Vaugh!) The effects are quite good. No surface scum. The water is clearer and probably cleaner. The fish seem livelier. No loss of CO2 (its off at night). seems like a win ....win .....solution!:D

The advice I got from Jack Wattley was to forget about pH, and its fluctuations, Discus are not that temperamental, that is a urban myth just leave the pH alone.

I hope this helps, I am not an expert, just one whom thinks Discus are THE most "regal",and "majestic" components of a home aquarium bar none!
 

Dmaaaaax

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Thank you The Rockster. So you use a pH meter and controller but still turn it off at night? So what is your pH right before lights our and first thing in the morning? With the controller is should be easy to see how much it changes. I assume yours probably fluctuates even more than normal since you are adding air at night?
 

Tom Barr

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The Rockster;32938 said:
Lately, I have been running air bubbles at night.(Thanks Vaugh!) The effects are quite good. No surface scum. The water is clearer and probably cleaner. The fish seem livelier. No loss of CO2 (its off at night). seems like a win ....win .....solution!:D

The advice I got from Jack Wattley was to forget about pH, and its fluctuations, Discus are not that temperamental, that is a urban myth just leave the pH alone.

I hope this helps, I am not an expert, just one whom thinks Discus are THE most "regal",and "majestic" components of a home aquarium bar none!

Jack's advice is spot on.
Of course I get zealots claiming otherwise even when respected breeders tell you otherwise, I can measure many things to see etc, but they are "correct"

He knows a lot about the fish and breeding, genetics etc, I know more general things about fish and toxicity, plants, etc.

But one method a lot of folks seem to do, I'm not so sure it's true, is coloration, they turn dark when stressed.

This can be for more than CO2 etc, color of the background, waking up/sleep etc. Many things. There might be something to it, and larger fish are more susceptible to CO2 issues than smaller fish as a rule.

I never had issues and they breed(Blue diamonds). I only kept them since I paid 5$ a fish.

Regards,
Tom Barr
 

abcemorse

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I'll second the discus opinion. I had discus and the pH changed from 6.8 to 6.2 or slightly lower everyday, no probs. i did learn, however, to do big water changes when the lights/CO2 are and have been off, because my tap water pH is quite a bit higher (7.2) than daytime tank levels, and the big increase then big decrease in the course of say, an hour or so, was hard on them, real hard on blue rams. Soon as I started changing water during non-CO2 hours stresses ended. HTH!
 

Dmaaaaax

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Thanks all...so I guess the next question would be, is there a negative to having the CO2 plugged into the pH controller and keep on 24/7....other than the fact that I am wasting CO2 at night when plants don't use it?

It's actually not as big of a waste though, since I don't have to ramp up the bubble count during the day to get the drop checker to light green.
 

Tom Barr

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I always do my water change before the lights come on or right after.
this way the entire time the lights are on, the tank has good nutrients that I just dosed and good CO2 from the tap.

Never an issue.
I know using a CO2 dissolved meter that 40ppm of CO2 has not observed effects over time on them. I install such a meter on client's tank and it's far more accurate than anything anyone else has and there's are lots of discus in the tank. He's also very picky about fish health and responses. So I think that's fine, 30-40ppm(if you can measure it that closely and without error).

I have never added CO2 at night, there's no need and pH is not the issue, the issue is adding CO2 only when it's needed for plants,. pH does not matter, Jack Wattley will tell you this, so will fish physiologist,m and so will I.

pH change via salts, not CO2(it's not a salt), are causes for more concerned however.



Regards,
Tom Barr
 

abcemorse

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I don't use a controller, just a timer and watch for pearling and fish stress, so I don't know if this is do-able or not, but I would think you could plug a timer into the controller, and the CO2 solenoid into the timer. That way, no waste at night and controller is functioning during the day.
 

shoggoth43

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I just picked up a milwaukee regulator and sms122 controller. I'm thinking of something similar in the 90 gallon range with either Angels or Discus.

So is the current "best method" for adding CO2 to use a simple timer with the solenoid? While I understand the point is to get the CO2 into the water and not to "control" the pH via the CO2, would it be inadvisable to use the SMS122 and just use the timer instead? I could easily plug the control outlet into a timer to keep it "off" during the night. I figure I bought the controller and it would be very annoying to just leave it lying around in a box. However, if there's no point in having it wired in, then KISS would be preferrable.

However, I'm currently only using a yeast generator on a BioCube8 and it's dropped the pH roughly a full point to 6.5. I'm not using a decent diffusor and just bubbling it straight into the pump chamber on the back. My guess is that because of the enclosed nature of the tank I end up with a layer of CO2 above the water in the pump chamber and in the biotower causing it to work better than I would otherwise expect. I don't do anything at night to offgas or otherwise stop the CO2 flow and I don't really see my pH change much.

It's still early in my attempts on this and don't have room for a reactor or diffusor so it's mostly proof of concept at this stage. I'm still reading up on the EI dosing and instead of water changes with distilled water to keep the hardness down I'm starting to use tap water and doing the changes a couple times a week until I get a better grasp on the dosing and get the proper fertilizers.

I've still got quite a bit of algae but I think I'm on the right track but I'm kind of dissapointed that I may have wasted a bunch of money on a pH controller I don't need and may not even use. I've already gone ahead and ordered a new needle valve and bubble counter and check valve to upgrade my regulator so I'm definitely learning.
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S
 

Gerryd

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IMO/IME I think eliminating the controller is a good thing. I think more folk are doing it, but you don't have to.

I used to have the same Milwaukeet/SMS setup. I eventually eliminated the controller and just use a separate timer for the c02 solenoid. Instead of the controller, I invested in a nice Hanna PH/Temp meter that helps me at a glance to see what's up. More accurate than the SMS anyway.

Have the c02 come on 30-60 PRIOR to lights on so that some c02 is available as the light is. Then off about 30-45 minutes PRIOR to lights off.

You can always run an airstone at night if you have room for another timer. This goes on when c02 is off.

I like the KISS method myself and this is easier. One less component you have to be concerned about.

Hope this helps.
 

shoggoth43

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Not quite the answer I was hoping for but simpler is better and will probably save me a pile of frustration in the long run. I may still use the controller but more as a pH monitor and use the timer for the CO2 control.

Not to overly hijack the thread, but has anyone been trying any of the refugia ideas with fresh water tanks? I was thinking of throwing some plants in the sump with a reverse lighting schedule to keep O2 levels up at night and this might help drop some of the CO2 levels in the tank overnight without "wasting" my CO2 by just blowing it off with airstones and whatnot. I'm not concerned with surface scum in the main tank as I'll be using an overflow to deal with that. With Gerry's advice I may just run the sump light for somewhat less time so I don't deplete too much of the CO2 and have to ramp it up in the morning before the lights come on so I get a decent level in the afternoon.
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S
 

Dmaaaaax

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Why do people try to get rid of the "extra" CO2 at night? If anything you get less pH swing and more starting CO2 in the morning if that "extra" CO2 stays in the tank. Am I missing something?
 

shoggoth43

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That's kind of what I'm trying to figure out. :)

I figure if I'm "supposed" to get rid of it, I'd rather have a reverse light cycle to at least give some benefit to the fish so they've got really good O2 and much less buildup of any ammonia. Otherwise it's just a waste of CO2 to blow it off with airstones or whatever. It certainly doesn't seem to be bothering my current fish to have the yeast injected CO2 constantly. I think I'm at such a woefully low level of CO2 in there it's not doing too much anyway, but I do get the pH swing if I stop it, so it's doing SOMETHING even if only keeping the water more acidic.
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abcemorse

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Plants don't need the CO2 at night, so first off it's just a waste of gas. Plus at night plants are actually releasing CO2 into the water, so turning the gas off makes things easier on the fish. The pH swings induced by CO2 are not much to worry about, really. The only trouble I've had is big WC during lights on hours, as the swing was big from low to high to low again in the course of an hour or so, and that only affected sensitive fish like blue rams and to a lesser degree discus. I don't do that any more.:rolleyes:

I think pH controllers are OK, only real prob I see is that for one to be effective, the bubble rate must be set at a rate higher than what you really want in the tank, otherwise it would never shut off, making itself obsolete. Therefore, if say, the solenoid fails and sticks open, you're running the risk of gassing the fish. Wtih the timer only config, the bubble rate is set to what the fish and plants are happy with, so if it sticks on there's not near as big of a problem.
 

shoggoth43

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Sounds good on the timer vs. the controller.

Thoughts on the reverse light cycle in the sump with plants? Waste of time and effort? I know the reefers do it but they usually have massive bioloads and it's part of their filtration. Seems like a neat idea that wouldn't be too hard to do, but if people don't think it's worth doing I'll skip it for now and maybe try it later on to see if I notice any benefits.
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S
 

VaughnH

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shoggoth43;33115 said:
Sounds good on the timer vs. the controller.

Thoughts on the reverse light cycle in the sump with plants? Waste of time and effort? I know the reefers do it but they usually have massive bioloads and it's part of their filtration. Seems like a neat idea that wouldn't be too hard to do, but if people don't think it's worth doing I'll skip it for now and maybe try it later on to see if I notice any benefits.
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S

Don't let us discourage you from experimenting with a planted sump system. The more things we experiment with the more we can all learn. I don't want to try that idea because of the added complexity it introduces, and the added room it would take, but I would be very interested to see how it works out if you try it.
 

shoggoth43

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I'll give it a shot. I'm still collecting all the parts for this so it'll probably be a while. I've got a friend who will help me build a stand and all that so it's mostly time and budget. Mostly budget at the moment. OTOH, I actually HAVE the wife's approval so that's a good chunk of the fight out of the way. :)
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Dmaaaaax

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abcemorse;33112 said:
Plants don't need the CO2 at night, so first off it's just a waste of gas. Plus at night plants are actually releasing CO2 into the water, so turning the gas off makes things easier on the fish. The pH swings induced by CO2 are not much to worry about, really. The only trouble I've had is big WC during lights on hours, as the swing was big from low to high to low again in the course of an hour or so, and that only affected sensitive fish like blue rams and to a lesser degree discus. I don't do that any more.:rolleyes:

I think pH controllers are OK, only real prob I see is that for one to be effective, the bubble rate must be set at a rate higher than what you really want in the tank, otherwise it would never shut off, making itself obsolete. Therefore, if say, the solenoid fails and sticks open, you're running the risk of gassing the fish. Wtih the timer only config, the bubble rate is set to what the fish and plants are happy with, so if it sticks on there's not near as big of a problem.


I wasn't saying to add more CO2 in my last statement above. I was asking why some people want to lower it faster at night by adding a bubbler. Why not just leave it alone? This would let you start with more CO2 first thing in the morning vs someone using an airstone at night which also means a smaller pH swing.

There is another reason for a controller. I use it as a safety backup. I found that my drop checker turns yellowish green at around 6.3pH, so by setting my controller around that, if I pump in too much CO2 it will shut off for a while. But I still try to get it close with the bubble counter alone. Typically the controller seems to only turn the CO2 off at night when the plants stop using CO2 and begins to release it.
 

Dmaaaaax

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As far as experiments go. Has anyone tried/made a thread where they used a sump with lights on 24/7 to try and isolate algae growth there? Basically by keeping the lights on and putting in a piece of driftwood or rock you promote the algae to grow in the sump rather than in your tank. The thought is that it is using up other nutrients (like silicates) so that your main tank does not grow algae....similar thinking to what some reef people do?
 

VaughnH

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Dmaaaaax;33128 said:
As far as experiments go. Has anyone tried/made a thread where they used a sump with lights on 24/7 to try and isolate algae growth there? Basically by keeping the lights on and putting in a piece of driftwood or rock you promote the algae to grow in the sump rather than in your tank. The thought is that it is using up other nutrients (like silicates) so that your main tank does not grow algae....similar thinking to what some reef people do?

I wouldn't expect that to work. That's because we don't get algae from excess nutrients. And, excess nutrients don't make algae grow better. Algae are so tiny, with so little mass, that they don't need much in the way of nutrients to grow well. I suspect, but haven't tried it, that you could put distilled water in a tank, put very high light intensity over it, with a rock or piece of wood in it, and algae would soon be growing there. You might need to add a tiny bit of ammonia to trigger the algae to start, but I'll bet it would grow well.