co2 regulator

hey guys,

i'm looking at getting co2, and like us all, i'm trying to sidestep the prices. We have family in Poland who are coming to SA for Christmas. Low and behold Co2 is CHEAP in Poland. according to me this is the same as what people generally use, but i wanted to run it past you lot to make sure, as it look a little different. it costs R180.

 

according to the site... (once translated)

SPECIFICATIONS:​

​

[HR][/HR]

First Type of gas - carbon dioxide / argon
Second Max inlet pressure bar / MPa - 200/20
Third Maximum outlet pressure bar / MPa - 4 / 0, 4
4th Nominal capacity - 25 l / min
5th Thread the nut on the outlet (hose end) - 6.3 mm FI 8mm6.Masa - 0.9kg- Maximum pressure set permanently: 3 bar
- continuous regulation of gas flow regardless of pressure in the cylinder
- continuous regulation of CO2, allows precise setting
(rotameter to set the gas flow very carefully even single bubbles)
- precision needle valve
- flow readings shown on rotametrze
- cylinder pressure reading on the manometer visible
- clear shield gauge
- pressure gauge in the cylinder to 300 bar
- very solid construction
- chrome plated surface​

 

Unfortunately, these are not the same. I have been searching this country for more affordable regulators, but I have not found anything for under R600... You need a needle valve for fine tuning the output of the Co2. Unfortunately it will not work, and it will need to be modified to give you bubbles per second and not liters per minute.

I am looking into cheaper regulators. I can get good quality ones for around R700. I'm just doing a bit more homework.

 

apparently it does have a needle valve. couldn't i just get a bubble counter? (or make one)

 

if it has a needle valve, and we can use it, count me in on the order list!!! GROOOOOOOT ASB!!!!!!

 

Make that times 2...

 

These cheap welders regulators are generally single stage and designed for short period application and the needle valves generally not capable of fine tuning down to the 3 bubble per second mark.

 

Check with @Zoom,

I am sure he have posted a DIY article somewhere on this forum for regulators & solenoids..

 

i think it will work. as for those who want to be on the 'order list', ill ask the family how many they can bring.

 

only problem with this is that it doesnt have a solenoid.. Switching on or off the regulator can become a pain. Not to mention what happens if ur lights go off and the co2 is still running?

 

Wow that's a good price and you can get the C02 tank from a welding supplier. I was going to look at injection, but went for the Hagen canister reactor (mix sugar and yeast), the C02 is then diffused via a bubble ladder.... in just 2 weeks my plants have exploded in growth and no more algae....love C02. The only thing with my setup is I don't have fine control over production as you do injecting... but this doesn't seem to be a problem at the moment. The other benefit of injecting is that once setup the tank will last months annd months, where as I have to create a new batch every two weeks. I can't recommend C02 enough for people with heavily planted tanks. Just watch your plants pearl!

 

Also, C02 running when the lights are off is not a major issue according to many - as long as your are not over 30ppm your fish will be fine.

 

Please explain why you say this?? This is possibly the most dangerous comment made on this forum. If the tank is sitting at 30ppm during the day, it will climb massivly during the night because the CO2 doesn't get used at night. Your pH swings will be HUGE. Your CO2 levels will be so high your fish will literally suffocate.

@Jay2theT PLEASE PLEASE PLEASE be careful with such flippant advice. In the few years I've been on this forum, I actually think you have officially given the most dangerous advice!

@EVERYONE... PLEASE disregard that comment about leaving CO2 running at night! (DIY yeast can be left running, because it's inneffective, but NOT pressurized CO2 if you have fish!!)

 

I will try to find and post, but I read an article by a tropical fish keeper with a docturate in chemistry who said that if you are running a DIY setup, then stopping the CO2 at night by either a solenoid or use of an air stone was not required and that actually trying to do so can cause the tank to switch level by extremes.... where as if you leave it running, then yes the levels go up a night, but it will not harm your fish. the document contained all sorts of ppm examples etc - as I said I will try to find it again and post, but I am new to C02 and so would really like to know the truth and what to do. The actual Hagen website which discusses the set up I have, also says nothing about having to stop the C02 production at night (or by pass it from the tank)

To everyone of the forum, apologies...I was refering to my Hagen DIY setup and the documents I've read and not referring to pressurised which I know if completely differnt....sorry

I also did say that as long as your tank is not over 30ppm it should be fine... yes if this is the case in the day, then night levels will go up, but again (and I know I didn't make this clear) my DIY setup doesn't exceed this level at night...

perhaps I'm better at just readin post and not giving advice.....sorry again for any upset.

 

I had a pressurized Co2 system on my tank, before I quit fresh water and moved over to marine tanks. This was the reason I moved to marines.

My timer failed. And my Co2 did not switch off. I woke up the next morning to find 6 Apistogramma trifasciata, 4 x keyhole cichlids, 2 x breeding pairs of bolivian Rams, 15 Rummy noses, 12 corys and some cherry barbs all dead. The Co2 killed my entire tank. Not one fish survived.

So, before you make wild generalizations, be VERY careful. Co2 is not a toy, and can be extremely dangerous! If it is not used properly, you run some very serious risks.

 

Hey Zoom,

I found the article if you wanna ready - would love to know your thoughts... from a biological / respiratory perspective it makes sense:


There have been a plethora of postings recently that demonstrate a pretty
clear misunderstanding of CO2, respiratory systems, O2<->CO2 relationships
and KH/pH/CO2 relationships.
I'm saying you do NOT want to turn off the CO2 at night, IMHO.
> I guess I am asking the basic
> question of - does [using a solenoid to turn off CO2 at night] sound
> reasonable?
No, IMHO.
> If I run it
> continuously, my pH will be lower at night than during the day when the
> plants produce O2.
Better stated as "The pH will be lower at night with the CO2 on because the
plants are not photosynthesizing and using their share of CO2."
> However, if I run against the timer, the pH will
> probably increase during the night due to the lack of CO2.
It will *definitely* increase at night. In a reasonable tank set up with
proper
water circulation, ALL the dissolved CO2 will dissipate into the atmosphere.
Check out my article "CO2 loss in a large aquarium" on my web page or the
krib
archives.

Take an example. Consider a typical setup with proper CO2 injection. A
reasonable set of parameters is 5 dKH and 15 mg/l of dissolved CO2
establishing
a pH of 7.0. With the CO2 turned off overnight, dissovled CO2 will be
reduced to a typical equilibrium value of 1.5 mg/l, creating a pH of 8.0!
That's quite a pH swing daily. I would not consider this a good environment
for fish.

> I like the
> idea of the timer for a few reasons. First, it gives the fish a break
> during the night when O2 will be lower because the plants are not
> contributing;

With proper water circulation, O2 levels will not drop appreciably overnight.
Although I've seen reports on APD where someone's fish were distressed,
presumably by a lack of O2, I've never seen this confirmed by anyone who paid
the least bit of attention to what was going on. I would attribute these
reports to a newbie hacking around with CO2 and water chemistry and water
movement (creating generally horrible conditions in the tank) and then
blaming the problems on CO2 injection.

In our one tank with manual CO2 injection running continuously, we would
see O2
saturation vary from around 120% in the evening to 90% in the morning
before the lights came on. Given that you can generally only achieve 95% O2
saturation even with the best airstones running full blast, going "down" to
90% at night isn't all that much of a drop.

Remember, there is no relation between the amount of O2 and the amount of
CO2 in the water (within reason). The O2 level in the water is determined
by diffusion at the water surface, proper circulation (mixing surface water
and lower water), the amount used by the aquarium bio-life and the amount
contributed by photosynthesis. Turning off CO2 at night does nothing to
prevent O2 from dropping. O2 is going to drop when the lights go out since
the plants stop photosynthesizing.

Your fish are going to get stressed only if CO2 increases TOO much
overnight or
the O2 is reduced TOO much overnight. Even with high oxygen levels, fish
cannot
respire CO2 unless the concentration of CO2 in the water is less than the
concentration of CO2 in the fishes blood. The exchange of O2 and CO2 in the
gills is determined by the relative concentration of each gas on both sides
of
the gill membrane and the exchange of each gas at the membrane is
independent of the other.

Many people miss this point. With high O2 AND high CO2 in the water, CO2
cannot
leave the blood (meaning O2 can't enter the blood; they bind to the same
site on the hemoglobin molecule) and the animal asphyxiates. With low O2
AND low CO2 in the water, CO2 can leave the blood but O2 can't enter and
the animal
asphyxiates.

> Second, it should save CO2.

The amount of CO2 you save is not really worth considering when you figure
what
CO2 costs (assuming pressurized CO2 bottles). I would venture a guess that
the
cost of the solenoid will be far greater than what you would save in CO2
costs
over many years of operation.

Also, consider the dynamics of the situation. Assume we start at a steady
state
CO2 level in the evening, save 15 mg/l. The lights are on, plants are
bubbling, O2 is high, everybody is happy.

Now the lights go off. CO2 stops and the dissolved CO2 starts dissipating.
Since the level in the water is far above equilibrium values, the
dissipates rapidly at first, causing a fairly quick rise in pH (maybe 0.5
points over two hours). O2 also starts to dissipate. However, fish and
plants are going to sleep, presumably requiring less O2 as they go into a
resting state.

Now it is morning and the lights come on. The fish and plants wake up,
increasing the demand for O2. The CO2 comes on, but wait! There is very
little
CO2 in the water and, since we aren't using an efficient CO2 reactor (since
there is no control over how fast CO2 dissolves except for the "slow bubble
rate"), it takes maybe hours for the CO2 level to reach the threshold where
the
plants can begin synthesizing. So, for the first period of time, everything
is
demanding more O2 but the plants aren't yet contributing any.

On the other hand, if the CO2 was running all night, there is now a little
higher concentration of CO2 than in the evening and the plants can
photosynthesize like gang-busters shortly after the lights come on.

Also consider the dynamics of CO2 usuage. The are two ways CO2 is removed
from
the water: dissipation into the atmoshere and usage by the plants. I have not
directly measured this, but I conjecture that the amount used by plants is
far
less than the amount lost to the atmosphere. This means that the
concentration
in the water during a 24 hour cycle only changes by the amount the plants are
actually using. The concentration goes down a little during the day and
goes up
a little at night, causing a far smaller pH change than if you turned CO2
off at night (a difference of 0.3 in our case).

 

OK, the article doesn't make mention whether it's DIY or Pressurized. DIY IMHO can be left on all night because really, it's totally inneffective and useless. It may work on small tanks, but it fluctuates too much and causes far too much water changes.

Pressurized CO2 should be turned on about 20minuted before the lights go on. Thus as the lights go on, the water has a higher level of CO2 instantly available for the plants. Then again, switch off about 20 mins before the lights go out, thus the lights use the remaining CO2.

pH swings are the biggest concern with CO2... and thus you need to be sure that your water chemistry is buffered correctly. With a higher gH and kH, you can buffer these swings to minimal.. if any. With DIY CO2, you cannot control this.

Also remember, that article is one man's opinion, and not the generally accepted rule world wide. I can almost guarantee that you will find 99.9% of commercially available CO2 pressurized kits will come with a solenoid... that's a given.

 

Can I ask why you say that DIY causes far too much water changes? I carry out a 10% change weekly.... should I be doing more?

I also get that the pressurised system allows more control (and one day I will go to this) but why do you say the DIY ones are inneffective and useless.... my tank is 180 Ltr... would you say this is ok for the Hagen? (1 bubble per second, but fully diffusing and no bubbles leaving the ladder and breaking the surface) my plants are doing very wekk since I started it.

 

I don't think that zoom meant too many changes. He meant too much fluctuations. The amount of co2 produced by a DIY kit increases and decreases depending on the temperature. The hotter the weather, the more co2 produced. The cooler the weather the less co2 produced. It is impossible to accurately control the amount of co2 produced in a DIY kit, which will lead to fluctuations of dissolved co2 in your tank. Which in turn, could lead to some nasty algae issues, like Black Beard Algae, which is a pain in the you know what to get rid of.

As for doing 10% water changes once a week, on a planted tank that you are dosing fertilizers in, that is not enough, in my opinion. If you are adding ferts, you should be doing nothing less than 30-50% water changes weekly. You are building up ferts in your water, which will cause algae issues as well...

Please just remember that we are trying to help. We're not trying to be overly critical, we have been through this before, and we have learned from mistakes made.

 

Cool thanks for the advice.

I will increase the % on weekly water changes.

I had heard that in the winter months my DIY CO2 would slow down. I hope I can get a pressurisd system by then