# Snails and C02 calculations



## ForestDave (21 Mar 2021)

Hi. 
Are some snails more reactive to CO2 than others? 
I have 2 rabbit snails, and 2 horned nerite snails. On Monday I bought 2 red onion snails and 2 striped nerites. The striped nerites struggled with the CO2 and died. I have been calculating the CO2 levels by D/C and KH/PH measurements off of the chart. Admittedly I am just trying to find the right setting but the day before yesterday I kept the CO2 no higher than 22.6ppm, (KH 3,  PH 6.6,  (down from PH 7.7 before CO2 was turned on)). One snail died that day. Yesterday I was caught out for an hour as I hadn't realized the KH had risen to 4 overnight from the rocks in the tank I presume and the ph dropped to 6.5 so CO2 was 37.9 for an hour until I realized the problem. 

The thing that I'm struggling with is my KH test only goes up in steps of 1. Is there a more accurate KH test out there as otherwise, you could be way out on the CO2 levels and not know it. My D/C always seems to be lime green and not yellow so I am not finding that much help. My plan is to keep it around 6.7-8 PH today which would put me in the 23.9-19 ppm range hopefully.
Either way are some snails more reactive or could it be that they came from a non-CO2 tank and needed more time to adjust? All of my other snails seem to be ok. 
I know cheap test kits are frowned upon but I've included the details anyway. (NT labs test kit).

Tank 200L
4 weeks old although FX6 filter has been running for 2 months, (4 weeks with plants and no substrate).
Ammonia/Nitrite 0
Nitrate, 0ish. Pretty much running clear on the test with the very slightest pink hue if you strain your eyes.
KH 3-4
Tap/tank water 7.7ph
Dennerle Scapers soil
Mini Landscape Rocks
Temperature 23 degrees C
EI fertz, 40ml macro/micro on alternate days basic APF mix for the moment.
4ml of Glute
Only have the 6 snails which are mentioned above and tiny bladder snail invaders.
The only algae issue so far was some green thread algae spirogyra on some high up weeping moss. I removed the moss so I could blackout and nutrient starve it separately and that is all cleared up now and ready to put back in.
Lights are 2x 38w T5. for 6 hrs per day, for the moment. The front one has a reflector on it as my carpet plants needed more light. 
Water changes have been 50% every other day for the last 2 weeks and every day before that.

Any tips welcome!
Thanks
Dave


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## Zeus. (21 Mar 2021)

I have had all my snails at top of tank with high CO2 in my 50L when I had forgotten to clean the eheim skimmer before holiday, lost quite a few RCS, had no fish in tank. Just like all other inmates every species has limits.

I take it the only reason you trying to get a higher [CO2] is..



ForestDave said:


> The only algae issue so far was some green thread algae spirogyra on some high up weeping moss.



If so get some Amanos, I would have some RCS as well. Snails and shrimp just make a more comprehensive clean up crew IMO


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## ForestDave (21 Mar 2021)

Zeus. said:


> I have had all my snails at top of tank with high CO2 in my 50L when I had forgotten to clean the eheim skimmer before holiday, lost quite a few RCS, had no fish in tank. Just like all other inmates every species has limits.
> 
> I take it the only reason you trying to get a higher [CO2] is..
> 
> ...


Thanks again, Zeus. 
I only got the ph pen fired up this week, before that, I was just using the D/C.  I'm not trying to get super high CO2 just an adequate amount. I was wondering about how to prevent the weeping moss algae with it being on a branch high up near the T5s. Hopefully now it is algae free and the tank has more plant growth it should be fine with the right amount of CO2. 
 I will be fitting my revised DIY CO2 reactor in a couple of days, so I am just having a practice run on doing the PH profile before I have to do it all over again when the reactor goes in.  I never realized it was such a fine line keeping the CO2 just the right level! I suppose oxygenating the water with an air stone during the photoperiod would probably off-gas more CO2 and complicate matters further?
Shrimp are definitely next on the list once the CO2 is dialed in.
Cheers.


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## dw1305 (21 Mar 2021)

Hi all,


ForestDave said:


> Are some snails more reactive to CO2 than others?


You've got two different factors. Snails from hard running water, or <"large calcareous lakes"> (like the Nerite and Rabbit snails) will have  no physiological adaptations to deal with high CO2, they come from hard water where the Total Inorganic Carbon <"(TIC) is always in the form of bicarbonate ions">.

Snails from heavily vegetated lakes (like Ramshorn and Tadpole snails) will have some adaptations, because there are going to be wide fluctuations in pH level as changes in the CO2:O2 ratio occur and in warm still conditions in the summer the CO2 levels may rise high enough to convert some of the TIC to CO2, even where you have naturally hard carbonate rich water.

The UK Nerite sp. <"Theodoxus fluviatilis"> would also have very limited capacity <"to survive in softer water">.

The other factor is that snails can only make <"shell at the mantle">. There is a more complete discussion in <"Nerites in a high tech">.

cheers Darrel


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## Wookii (21 Mar 2021)

I would ignore the pH/KH table and trying to calculate your absolute PPM levels of CO2 @ForestDave, it’s fraught with error.

Rely only your drop checker to tell you that you have the right level of CO2 (accounting for the 2 hour delay), that’s why it uses a constant 4dKH solution. You pH pen can then be used as confirmation to ensure you are getting a 0.8-1.0 pH drop.


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## ForestDave (21 Mar 2021)

Wookii said:


> I would ignore the pH/KH table and trying to calculate your absolute PPM levels of CO2 @ForestDave, it’s fraught with error.
> 
> Rely only your drop checker to tell you that you have the right level of CO2 (accounting for the 2 hour delay), that’s why it uses a constant 4dKH solution. You pH pen can then be used as confirmation to ensure you are getting a 0.8-1.0 pH drop.


Thanks Wookii 👍


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## ForestDave (21 Mar 2021)

dw1305 said:


> Hi all,
> 
> You've got two different factors. Snails from hard running water, or <"large calcareous lakes"> (like the Nerite and Rabbit snails) will have  no physiological adaptations to deal with high CO2, they come from hard water where the Total Inorganic Carbon <"(TIC) is always in the form of bicarbonate ions">.
> 
> ...


Thanks, Darrel. 
You certainly know your stuff!
I put a small piece of cuttlefish bone in the tank hoping they would chew on that to boost their calcium reserves. My daughter got into keeping garden snails and they would chew on them if their shell became soft or damaged or simply to grow new shell. It sounds like that may be a waste of time from what you're saying if the acidic water dissolves their shells and they can't repair them as a garden snail can?


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## sparkyweasel (21 Mar 2021)

dw1305 said:


> Ramshorn and Tadpole snails


It may also be relevant that these can breathe air, whereas Nerites (and I think Rabbit Snails) can't.


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## dw1305 (21 Mar 2021)

Hi all, 


ForestDave said:


> My daughter got into keeping garden snails and they would chew on them if their shell became soft or damaged or simply to grow new shell. It sounds like that may be a waste of time from what you're saying if the acidic water dissolves their shells and they can't repair them as a garden snail can?


Terrestrial snails can repair mechanical damage to their shells to some degree. I assume because the dried mucus sticks the shell back together and the mantle can then secrete new shell  on the inside of the shell.  The calcium  carbonate they secrete comes from their food source.

They can only repair their basal shell whorl (the< "mantle cavity">), where the snail is resident. The older shell whorls, towards the apex <"can't be repaired">.





From <"Biological Diversity 8">

I have soft water, and I even the Red Ramshorn Snails in my tanks don't grow very large, and have very fragile, white shells. MTS survive in some tanks, but again they never grow very large and show <"shell attrition to the older whorls">. 

cheers Darrel


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## jaypeecee (21 Mar 2021)

ForestDave said:


> The thing that I'm struggling with is my KH test only goes up in steps of 1. Is there a more accurate KH test out there...



Hi @ForestDave 

I don't know that you'll need it in this instance but should you ever need a more accurate/higher resolution KH/Alkalinity Test Kit, I find the following to be pretty good:






						KH Test Pro | Produktinformationen
					






					www.tropic-marin.com
				




I use this test kit to make up my KH4.0 DC solution.

JPC


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## ForestDave (22 Mar 2021)

jaypeecee said:


> Hi @ForestDave
> 
> I don't know that you'll need it in this instance but should you ever need a more accurate/higher resolution KH/Alkalinity Test Kit, I find the following to be pretty good:
> 
> ...


Thanks. That looks like useful stuff. So your drop checker changes different colours to the standard blue green yellow offerings.


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## ForestDave (22 Mar 2021)

Thanks @dw1305 !


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## ForestDave (22 Mar 2021)

ForestDave said:


> Thanks. That looks like useful stuff. So your drop checker changes different colours to the standard blue green yellow offerings.


Ah, I probably got that wrong. You use the Tropic Marin KH test to ensure you have an accurate 4dkh solution to add the DC liquid to...


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## dw1305 (22 Mar 2021)

Hi all,


ForestDave said:


> You use the Tropic Marin KH test to ensure you have an accurate 4dkh solution to add the DC liquid to...





jaypeecee said:


> I use this test kit to make up my KH4.0 DC solution.


You can do much better than that in terms of accuracy. You can actually make a known "4 dKH" solution and then use that as a standard to calibrate the Tropic Marin KH test against.

You can make an exact 4dKH solution by dissolving 6g of pure sodium bicarbonate (NaHCO3) in DI water and then making this up to 5 litres (in RO) to give you a 40dKH stock solution.  Then using <"serial dilution">, and adding 100ml of the stock solution,  to 900ml of DI water will give you 1000 mL (one litre) of 4dKH reference solution.

The workings are from <"Water Hardness">.


> .........If you want to raise the alkalinity by 1dKH using NaHCO3:
> 
> RAM of sodium (Na) = 23
> RMM of bicarbonate (HCO3) = (1 + 12 + (3*16)) = 61
> ...





> (21.8 *84)/61= 30 mg/L of NaHCO3
> 
> 1dKH = 21.8 ppm HCO3.......



Because these are dilute solutions you can assume that one mL weighs one gram and just use digital scales to get accurate volumes.

cheers Darrel


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## Wookii (22 Mar 2021)

Or you can do what those of us a little lazier in inclination do, and just buy pre-made drop checker solution:









						CO2 Check 30mg 250 ml
					

Water tester. Price: £15.69. Content: 250 ml. Free delivery from £42.90. Delivery in 5 days.




					www.olibetta.uk
				




I only change mine every few months, so that bottle is enough for quite a few years.


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## ForestDave (23 Mar 2021)

On the snail/ph subject I've managed for the last few days to limit the ph drop to between 0.8 and 1ph as @Wookii suggested and all of my other snails seem totally fine with that. 
Thanks, all, for the advice!
Loving the snails at the moment. It's great seeing what they all get up to.


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## Tom72 (2 Apr 2021)

ForestDave said:


> Hi.
> Are some snails more reactive to CO2 than others?
> I have 2 rabbit snails, and 2 horned nerite snails. On Monday I bought 2 red onion snails and 2 striped nerites. The striped nerites struggled with the CO2 and died. I have been calculating the CO2 levels by D/C and KH/PH measurements off of the chart. Admittedly I am just trying to find the right setting but the day before yesterday I kept the CO2 no higher than 22.6ppm, (KH 3,  PH 6.6,  (down from PH 7.7 before CO2 was turned on)). One snail died that day. Yesterday I was caught out for an hour as I hadn't realized the KH had risen to 4 overnight from the rocks in the tank I presume and the ph dropped to 6.5 so CO2 was 37.9 for an hour until I realized the problem.
> 
> ...


How long are you running your CO2? When I first started I micro managed and tested everything and it was stressful. These days I just go on observation and I have less worries. I am running a 40ltr, which is running CO2 at approx 1.5 bps. I have 3 nerite snails and they are doing perfectly fine, as are the rest of the inhabitants and I have a PH of . Do you have many other inhabitants or is it just the snails? As a general rule I follow 1 bubble per 50ltrs ( a tip I picked up from somewhere) so I am over that, and my dropper checker is light green. It might be that your looking in the wrong place and it could be something parasitic or other snail disease which is already present when you bought them. How long did you acclimate the snails, they should be acclimatised very slowly as they are very sensitive to change if they were introduced to fast  that could have shocked them and caused their demise.


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## Tom72 (2 Apr 2021)

PH of 7


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## ForestDave (2 Apr 2021)

Thanks Tom. 
I don’t know what the problem is. I am going for a drop of between 0.8 and 1 ph. That’s consistent like clockwork now. I have 2 small nerites and a red onion snail which have always been fine and active and 17 shrimp have been in there a couple of weeks. They all seem fine. My two rabbit snails are not happy though and are in a isolation tank at the moment. I don’t think the CO2 is the problem as the rabbits were fine for 4 weeks then they lost all energy and would lie on their backs. One is  a bit jumpy flinching in and out as you get close.


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