Too much CO2 mist?

[Neil Frank]

I am wondering if i may have been injecting too much CO2. Although fishes have been OK, plant growth is not what i anticipated in this new tank with ADA Amazonia.

I am using Needle Wheel to inject CO2 into my sump pump. the 180g tank, sump and co2 system are all new and only in operation for 60 days. After the CO2 tank depleted (too quickly) i started to wonder if my bubble rate may have been too high. So with new CO2 tank, i cranked down the bubble rate. It is now a few bubbles per second. Before it was too fast to even count. I set that bubble count to lower the pH to 5.9 to 6.0 which the chart suggested was the level to achieve 30ppm. Old pH in sump was 5.9, new pH is 6.3. Tank pH is lower, so use the change as a relative indicator of less dissolved CO2. (without any CO2, I think the sump pH reaches 6.6).

I checked the Barrreport archives on mist, and there is discussion that pH may not be a good indicator of available CO2 . There is also suggestion that the mist may no longer be CO2 and it has all dissolved on or before it hits the tank water (we may be looking at O2 or Nitrogen gas)


Although too soon to be sure, it seems that the plants are pearling more with less CO2!

My question is: Although i might not have been provding too much CO2 to adversely affect the fish, could it be too much for the plants. One of my plants in particular has not be growing well since its introduction into the new quarters -- Echinodorus horemanii -- several specimens of it. I have been keeping this speciies for 15 years, and these clones almost stopped growing in the new tank. During the first week, the leaves became chlorotic (transparent). I played with tank chemistry and over the past 60 days, they have slowly started to take off. With the lower CO2 bubble rate thru the Needle wheel pump, their leaves are covered with O2 bubbles! I initially suspected a response to the Amazonia's acid substrate . Now i am thinking that the high CO2 rate may be the culprit.

Tom and others, WDYT? Please provide comments and experiences with mist CO2, or point me to other discussion on the BarrReport. Thanks! Neil

 

[Gerryd]

Hi Neil,

A couple of thoughts.

Plants do require 02 as well as c02, so it may have been insufficient 02 rather than too much c02 if that makes sense. I have read other threads here
where folks report better pearling after injecting 02 in some manner or the other............

Have you sealed your sump and reduced the waterfall in the overflows? My 180 was sump and wet/dry before I went closed loop/canister. Always had issues with c02/pearling and the tank never lasting very long............

This may be why your tank requires a higher bubble rate?????

Has the tank cycled? I know that ADA leaches NH4 in the water for a long time and this could interfere with growth.......

PH by itself is not a good measurement of c02. Have you investigated the use of a drop checker filled with de-ionized water to help determine your c02 levels?

How much light/duration are you providing? Could it be too much light and not enough nutrient levels? Are you dosing EI at all or any macros/micros?

Hope this helps.

 

[Neil Frank]

Hi Neil,

A couple of thoughts.

Plants do require 02 as well as c02, so it may have been insufficient 02 rather than too much c02 if that makes sense. I have read other threads here
where folks report better pearling after injecting 02 in some manner or the other.............

Hard for me to believe insufficient O2, with the overflow and sump, but i am not rejecting any ideas.

Have you sealed your sump and reduced the waterfall in the overflows? My 180 was sump and wet/dry before I went closed loop/canister. Always had issues with c02/pearling and the tank never lasting very long..............
This may be why your tank requires a higher bubble rate?????..............

i have only partially sealed the sump. and could be a reason that i am loosing CO2... if in fact, i needed that much to begin with. I still intend to seal the sump and even raise my Dursos, but have not gotten around to it.

Has the tank cycled? I know that ADA leaches NH4 in the water for a long time and this could interfere with growth.......

good point. But, Yes it did! I didnt have fish for first 30 days. Plants from day 1. I checked NH4 at day 30 and it was zero. However, I did not check how high the NH3 was initially, and although most plants did very well, it is conceivable that the E.horemanii was more sensitive to high ammonia, perhaps even toxic for that species. On the other hand, many other plant species have been reasonably good.

PH by itself is not a good measurement of c02. Have you investigated the use of a drop checker filled with de-ionized water to help determine your c02 levels?

I agree, and i didnt used DC, but i tried to consider KH. ... and effect of tannic acids from AS. I was using relative change in pH and not the absolute levels. I allow for the possiblity that CO2 levels were much greater than 30ppm. Still, could that be harmful to plants and not the fish. Hard to believe, but....

How much light/duration are you providing? Could it be too much light and not enough nutrient levels? Are you dosing EI at all or any macros/micros?

12hrs, 320w T5 HO Tek light (should be sufficient). I did suspect possibly low nutrients, so i dosed NPK , Ca and traces. Also was doing daily water changes for 1st 2 weeks, then less frequent. So, i tend to doubt insufficient nutrients. But still am wondering if the CO2 by itself could be a factor.

 

[Tom Barr]

Hard for me to believe insufficient O2, with the overflow and sump, but i am not rejecting any ideas.

I'd rule this one out.

i have only partially sealed the sump. and could be a reason that i am loosing CO2... if in fact, i needed that much to begin with. I still intend to seal the sump and even raise my Dursos, but have not gotten around to it.

Going back to Steve, George and my wet dry issues from the 1990's, these are huge issues. Neither of us saw any movement of pH till we fiddled with each: the overflows and air into the dry part. Overflow alone accounted for most of the losses, but depending on the seal and level in the sump, the dry part could make a large difference.

I tried a dozen modifications so I could use those filter socks they use for reefs, but even using a degassing regasser tube, still at 10-15 bubbles a second on a tank that should be about 4-5 bubbles a second tops, could not keep up.

So I am installing a CPR wet dry today
Removed the sump and berlin style system.
Back to basic methods.

If I want more mechanical, a post canister would take care of that, or have an independent canister loop filter etc.

good point. But, Yes it did! I didnt have fish for first 30 days. Plants from day 1. I checked NH4 at day 30 and it was zero. However, I did not check how high the NH3 was initially, and although most plants did very well, it is conceivable that the E.horemanii was more sensitive to high ammonia, perhaps even toxic for that species. On the other hand, many other plant species have been reasonably good.

Some species will melt, unless you do 2-3x a week 50-70% water changes for the first 4-8 weeks, even then..........some do.

I agree, and i didnt used DC, but i tried to consider KH. ... and effect of tannic acids from AS. I was using relative change in pH and not the absolute levels. I allow for the possiblity that CO2 levels were much greater than 30ppm. Still, could that be harmful to plants and not the fish. Hard to believe, but....

ADA will depress the pH, typically 5.5-5.8 are normal.
You might just eye ball the plants and fish.

You can blow out the water by doing a 80% water change back to back, then measure the KH/pH. Most of the KH will be accurate as will pH and less effect on tannins. Adding activated carbon will help the tannins. So a little of both can get things pretty good. Riccia is a good indicator for pearling.

12hrs, 320w T5 HO Tek light (should be sufficient). I did suspect possibly low nutrients, so i dosed NPK , Ca and traces. Also was doing daily water changes for 1st 2 weeks, then less frequent. So, i tend to doubt insufficient nutrients. But still am wondering if the CO2 by itself could be a factor.

Go 10 hours. Mg dosing?
I'd dose pretty good from here on.
NO3, K+, PO4, Traces, GH...........

Then the rest is CO2.

Regards,
Tom Barr

 

[Neil Frank]

I'd rule this one out.
Going back to Steve, George and my wet dry issues from the 1990's, these are huge issues. Neither of us saw any movement of pH till we fiddled with each: the overflows and air into the dry part. Overflow alone accounted for most of the losses, but depending on the seal and level in the sump, the dry part could make a large difference.

I tried a dozen modifications so I could use those filter socks they use for reefs, but even using a degassing regasser tube, still at 10-15 bubbles a second on a tank that should be about 4-5 bubbles a second tops, could not keep up.

So I am installing a CPR wet dry today
Removed the sump and berlin style system.
Back to basic methods.

Hmm... what is CPR wet dry? Although i have been having fun playing with an entirely new technology, some days i think i should have stuck with my old methods too. The overflow noise, internal space it takes, CO2 issues, etc, make me wonder if my costly "experiment" was worth it.

If I want more mechanical, a post canister would take care of that, or have an independent canister loop filter etc.

I am using large thick Poret sponges in the sump and they do great job with mechanical filtration, albeit maybe too much biological. They also allow me to partition the middle section of sump so i can use it as holding tank for fish and plants.

Some species will melt, unless you do 2-3x a week 50-70% water changes for the first 4-8 weeks, even then..........some do.

I forgot to mention that i did daily 50% water changes for the first month. then 2-3x week since. Not counting crypts, most plants did not melt. The crypts are still not growing well, at least compared to non-ADA soil 60 day setups.

ADA will depress the pH, typically 5.5-5.8 are normal.
You might just eye ball the plants and fish.

I did.... and kept tweaking the CO2 thinking that more was better. The fish are all great, loving the low pH, high tannin water. Several spawns in the first month!

You can blow out the water by doing a 80% water change back to back, then measure the KH/pH. Most of the KH will be accurate as will pH and less effect on tannins. Adding activated carbon will help the tannins. So a little of both can get things pretty good. Riccia is a good indicator for pearling.

Go 10 hours. Mg dosing?

Why 10? Slow down plant growth and to balance the available nutrients. I could also run half the bulbs for fewer hours. I finally added a bag of carbon when i wanted the water to clear. I was afraid to do it too early for fear of introducing another variable and adsorber of nutrients.

I should have mentioned Mg. I use dolomitic lime for both Ca, Mg and CO3.

I'd dose pretty good from here on.
NO3, K+, PO4, Traces, GH...........
Then the rest is CO2.

So Tom, do you think that too much CO2 could be bad.... and less could be better...... perhaps, just like too much light without not enough other nutrients. I have not been provding a lot of extra nutrients yet.

Regards, Neil

 

[Tom Barr]

Hmm... what is CPR wet dry? Although i have been having fun playing with an entirely new technology, some days i think i should have stuck with my old methods too. The overflow noise, internal space it takes, CO2 issues, etc, make me wonder if my costly "experiment" was worth it.

That makes two of us.
But new stuff needs tested and tried.
I'm pretty much done at this point though.

The sump with a traditional wet/dry chamber works best it seems to me.
That's what I use to use. Hardly needs cleaning and the load from planted tanks is a lot, too much for most of the filter socks for many tanks.

I am using large thick Poret sponges in the sump and they do great job with mechanical filtration, albeit maybe too much biological. They also allow me to partition the middle section of sump so i can use it as holding tank for fish and plants.

Those are great, that's all I use.
But I have a wet/dry chamber where water first comes in and I plug the holes up with duct tape.

Client's tanks are similar.

I forgot to mention that i did daily 50% water changes for the first month. then 2-3x week since. Not counting crypts, most plants did not melt. The crypts are still not growing well, at least compared to non-ADA soil 60 day setups.

Most of the plants should do fine, otherwise it's a CO2 issue.

I did.... and kept tweaking the CO2 thinking that more was better. The fish are all great, loving the low pH, high tannin water. Several spawns in the first month!

Well, there's few other reasons why the tank would not be doing well with plants other than nutrients and CO2, the nutrients are easy to rule out via dosing and water changes(which you have been doing anyhow).

So that leaves just CO2.
Careful with the pH though and ADA AS, it messes with pH.

Why 10? Slow down plant growth and to balance the available nutrients. I could also run half the bulbs for fewer hours. I finally added a bag of carbon when i wanted the water to clear. I was afraid to do it too early for fear of introducing another variable and adsorber of nutrients.

I've honestly never found any relationship with nutrients and activated carbon, the carbon is more specific to large ions and organics, not these small nutrients.

The light is more based on what plants will use, you can see many closing up towards the 7-9 hour range. I'd run the lights low first then high and then low then off. Then repeat etc. Maybe 4 hours total max light midday.
The T5's are very bright, more than you think.

If you have ample biomass, then you can dose pretty rich nutrients, try 1/2 EI.
You can split it into daily dosing also, add to liquid etc, make similar to 2.5X PMDD but keep the Traces out and dose those separate and add the PO4 as well to the macro nutrient solution.

I should have mentioned Mg. I use dolomitic lime for both Ca, Mg and CO3.

I'd suggest trying the GH booster, it's about 1/2 K2SO4, 1/4 Mg and 1/4 Ca and a little Mn/Fe for good measure. Sort of a one stop cure all for the rest besides NPK and Traces.

Alan sells it, so do others, sort of like DIY pre made SeaChem Equilbrium.

So Tom, do you think that too much CO2 could be bad.... and less could be better...... perhaps, just like too much light without not enough other nutrients. I have not been provding a lot of extra nutrients yet.

Regards, Neil

No, not unless fish are stressed. Usign less light is how you do this, you do not start in the middle or the end to control nutrients or CO2 demand, you start with light, since light drives all photosynthetic processes.

So more light = more CO2 demand from plants, that in turn drives nutrient nutrient demand. So you have far more wiggle room, resiliency, stability etc, using lower to moderate light vs higher intensities.

This reduces CO2 demand from the plants, thus you have a much wider easier to achieve target for CO2, then the same is true for the nutrients, you can get away with a lot less, more, neglect etc.

It's common sense if you know how a plant grows and what % of it's components come from. Some ignore it and think that their observed correlations means everyone's must be the same.

But then you find counter examples that disprove it, they typically did not measure light and CO2, so all the brew haha over nutrients is really secondary effects, not root causes. That's why I can add loads of nutrients without issues, whereas others may or may not have issues.

ADA lights are very low over all, 30-50micromols along the substrate which is pretty low. I compared the methods and the LiCOR sphere 193 to the apogee many are now starting to use and it was within 5% or less error over 80 cm depths in our columns at the lab.

Good enough for me and cheap.

CO2 is the tricky one.
No good method to measure it that's cheaper than say several hundreds and DIY or 2000-3000$ for a pre made one( ihad one and then installed in a client's tank.
Pretty cool device.

But for 3000$, it better be.

It does not have any issues with pH/KH or any internal water parameters, just the CO2 dissolved and it's response time is about 2-4 minutes.

If you use a water sampling chamber that's sealed, you can withdraw water and avoid the response time entirely and measure down to 100microliter volumes(eg, at the surface of leaf vs 1 cm away etc).

Regards,
Tom Barr