# [Wet Thumb Forum]-SOft water, natural ph 6.5 Can I use co2 system



## sherry (Sep 30, 2005)

without having a hellish time buffering?

someone suggested eco complete naturally buffers..

someone else said not to start at all and to stick to excel

I need to figure this out!!

Robert says Roger was the one to ask. please help.


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## sherry (Sep 30, 2005)

without having a hellish time buffering?

someone suggested eco complete naturally buffers..

someone else said not to start at all and to stick to excel

I need to figure this out!!

Robert says Roger was the one to ask. please help.


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## Alberto Villarroya (Nov 15, 2003)

I presume you have low KH, in that case your C02 levels won't be great, if what you intend is to have enought C02 for the plants you can rise the KH level and inject C02. It's not difficult to achieve the desire KH.


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## Stevenl (Mar 31, 2004)

My water is about as soft as yours. To increase kH I add baking soda (sodium carbonate). A teaspoon of baking soda increases 50L of water by 4 degrees of kH, which is a good kH to achieve for Co2 injected plant tank. Also I think eco-complete does not increase kH

It's not difficult to increase kH...decreasing the kH is actually much more difficult..HTH!!

66G tank with 3 wpg NO Fluroscent,and 50/50 flourite substrate, UV sterilizer, DIY CO2 (upgrade soon!)


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## Roger Miller (Jun 19, 2004)

Sherry,

The responses you've had already are right. You really do need to increase the buffer capacity (KH) in order to inject CO2. If you don't then the pH will be too low. You probably want at least 3 degrees KH.

Increasing KH is one of the easiest water quality adjustment that you can make. That's because it is both easily measured and fairly constant.

You increase the KH by adding bicarbonate to the water. There are number of ways to add bicarbonate. What you find best will probably depend on your equipment, your maintenance schedule and you personal preference.

Probably the simplest way is (as StevenL said) is to use sodium bicarbonate -- baking soda (not baking powder, which has other additives). Baking soda dissolves quickly. You can work out how much you need to add to the water you use for water changes do that every time and then never really think about it again. As simple as that may seem it isn't the method that I find most advisable. Using sodium bicarb to increas KH can result in high sodium levels and in soft water it will give high sodium:calcium ratios that aren't great for plants.

I have never had to adjust the KH in my tanks, so this information is mostly second hand.

Dolomite is the best source of bicarb for a planted tank; that's because it provides not only the bicarb for buffering but also calcium and magnesium that are essential for healthy plants. Calcite in one of many forms is the second best source of bicarb for a planted tank. It is chemically similar to dolomite, but provides mostly calcium rather than calcium and magnesium. Some calcite does contain enough magnesium to be significant. Your experience will vary.

Dolomite (best used as chips, possibly as powder) is available from garden centers and places that sell soils and treatments for house plants. Dolomite is calcium magnesium carbonate. Calcite can also be had as limestone or marble chips from the same sources, as sea shells or as dietary suppliment tablets from the grocery store or pharmacy. Calcite is calcium carbonate, usually with a little magnesium included. Dolomite and calcite both dissolve slowly; calcite is a bit quicker than dolomite.

Shells or chips can be put into a mesh bag and placed somewhere out of sight in the aquarium. The shells or chips will gradually dissolve. You need to measure the KH and remove the bag when KH reaches the level you want. You may have to adjust the volume or frequency of water changes to get the results you want. Once you have the system down I understand that it is very easy to maintain good conditions.

The mesh bag can also be placed in a filter where it will gradually dissolve. In open wet-dry filters and hang-on power filters the bag can be taken out when the buffer capacity is where you want it. Canister filters are more difficult because it isn't convenient to open them up all the time. In that case you would need to leave the bag in the filter and adjust your water changes to get the result you want.

Powders are a little different. They don't dissolve very fast and can blow around for a while before it dissolves or settles down in an aquarium. Tablets work about the same way because they break down under water to powder-sized particles. I don't think that dolomite of calcite (limestone) powders are the best way to add buffer capacity, but they work.

You will probably find that adjusting the buffer capacity and using pressurized CO2 is a better alternative in the long run then trying to use a liquid carbon suppliment like Excel or Liquid CO2.

Roger Miller

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_"The indispensible first step to getting the things you want out of life is this: Decide what you want" -- Ben Stein_


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## sherry (Sep 30, 2005)

i like the dolomite idea....what sort of kh am i looking for?

btw, i just saw a gorgeous planted tank at a lfs that they say they maintain with carbo plus..


that is another option, and avoids the issues of a co2 tank around kids.

would the dolomite and the carbo plus thing work well together?


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## imported_Piscesgirl (Feb 19, 2004)

What about calcium cloride? (like found in Kent Marine Liquid Calcium)?


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## Roger Miller (Jun 19, 2004)

If you want to use compressed CO2 then you should probably have at least 3 KH. Just how high you go with the KH is up to you. For the most part you probably want to keep the KH below 24 degrees. Eight or nine degrees is a very good mid range. The higher you make the KH the higher the pH, all else being equal.

Carbo plus is a little controversial. The product brochure claims that the device works by converting the carbon block to carbon dioxide. Paul Sears claims that is not true. The device works by converting bicarbonate in the water to carbon dioxide. Most of the experience I've heard is consistent with Paul's conclusion. Paul is a chemist who is professionally involved in related subjects. I expect he knows what he is talking about.

Since you have no KH to speak of the Carbo Plus should do very little for you. To get much benefit out of the Carbo Plus you would need to continually monitor and add bicarbonate to replace what is used by the Carbo Plus. It makes the whole buffer problem 10 times worse. I have to wonder how much benefit the tank at the LFS really got from a Carbo Plus.

Also, Carbo Plus units are fairly large and the largest tank they can supply well isn't very big -- maybe 30 gallons. The ones I've seen in photos have been unsightly.

Calcium chloride will increase GH but does nothing for the buffer capacity (KH).

Roger Miller

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_"The indispensible first step to getting the things you want out of life is this: Decide what you want" -- Ben Stein_

[This message was edited by Roger Miller on Sun March 21 2004 at 07:21 PM.]


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## sherry (Sep 30, 2005)

which leaves me back to either messing with compressed... or trying excel.

do you think excel dosing can be sufficient?

i have 96 watts or will have 96 watts over a 30 gallon tank.. minus substrate vol and all that works out to more than 3watts per gallon

I'm a little nervous about compressed because I have a 2 year old... the only place to put a tank would be on top of fridge behind microwave...

Not totally against it.. but if excel would work... It would be safer.


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## Stevenl (Mar 31, 2004)

Roger: I use sodium carbonate to main my kH at 4 and I use kent marine calcium (cacl2) to maintain my calcium level at around 40ppm.

Do you think the sodium:calcium ratio would be not good for plants? I do that since day 1 of my tank and my plants are growing very well, but I am always looking for ways to grow my plants better.

Thanks,

Steven

66G tank with 3 wpg NO Fluroscent,and 50/50 flourite substrate, UV sterilizer, DIY CO2 (upgrade soon!)


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## Stevenl (Mar 31, 2004)

Sherry: Have you considered using diy yeast generated co2? It can provide enough co2 for your 30G tank, and is less dangerous than a pressurized co2 tank.

But the potential danger of yeast co2 in you case is that your child might accidentally knock down the bottles, and then the yeast solution might go into the tank.

66G tank with 3 wpg NO Fluroscent,and 50/50 flourite substrate, UV sterilizer, DIY CO2 (upgrade soon!)


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## sherry (Sep 30, 2005)

i could do diy.. It just seems like a messy way to go about it and everyone using it.. like you.. wants to upgrade


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## Roger Miller (Jun 19, 2004)

Steven,

Using baking soda to get 4 dKH means that you will be adding about 33 ppm of sodium. As long as your adding some calcium to balance that out you shouldn't have calcium problems. You might also add a little magnesium (epson salt). It wouldn't take much.

When you say you're adding enough to get 40 ppm, do you mean 40 ppm of hardness, or 40 ppm of calcium?

Sherry,

A two year old, eh. My kids weren't all that bad at two. I had multiple aquariums in the house but none with CO2. The worst problem I ever had was when my oldest was about 19 or 20 months. She decided to help daddy by feeding the fish. She dumped an entired container of freeze-dried brine shrimp into a 1.5 gallon aquarium. So much for my dwarf loaches.

I don't know what your setup looks like. Commonly the aquarium stand has a cabinet built in. You could add child-safe latches to the cabinet, strap a 5-lb cylinder against the inside of the cabinet so it can't be knocked around and run any tubing to the aquarium where the tubes are out of reach and/or can't be easily pulled out.

I always talked to my kids about the aquarium equipment, showed it to them and tried to make it so that it wasn't a curious mystery. I also tried to get across to them that bad things could happen if they messed with things. That may have helped, but different kids seem to respond differently to that approach. A CO2 tank isn't very interesting, but the regulator, bubble counter, reactor (if you use one) and tubing could be appealing.

I would avoid DIY CO2 for now.

I used Excel on my 38 gallon tank. It was a low light tank and the Excel worked very well. I didn't continue using it because it gets pretty expensive for a tank that large. I'm not sure that the light level has that much to do with using Excel. Maybe someone else around could advise you on using it with a brightly lit tank.

Roger Miller

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_"The indispensible first step to getting the things you want out of life is this: Decide what you want" -- Ben Stein_


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## Stevenl (Mar 31, 2004)

Roger: 40ppm of calcium and 10ppm of magnesium.

Yes epsom salt is what I add for the magnesium.

66G tank with 3 wpg NO Fluroscent,and 50/50 flourite substrate, UV sterilizer, DIY CO2 (upgrade soon!)


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## Stevenl (Mar 31, 2004)

Roger: 40ppm of calcium and 10ppm of magnesium

Yes epsom salt is what i add for the magnesium.

66G tank with 3 wpg NO Fluroscent,and 50/50 flourite substrate, UV sterilizer, DIY CO2 (upgrade soon!)


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## gump (Feb 19, 2003)

Could you mix the dolomite(granular form) in the substrate?


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## Roger Miller (Jun 19, 2004)

It is possible to put dolomite in the substrate, but the resulting hardness might be difficult to control.


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