Looking for Reccomendations/Suggestions

[aberg12012]

Ok... here's a question. What does "soft" or "hard" water ACTUALLY mean? I've alwyas thought high KH meant soft water... like that of my reef aquarium which I keep around 10 dKH.

 

[ksimmo1]

There is a method of calculating concentrations of CO2 by KH and pH. Search the web, lots of tables and even calculators exist there. CO2 tests are also comercially available. Be shure that your water is hard enough to buffer pH on CO2 injection. If water is soft, inject CO2 carefully, as you can take pH down below 6 easily in soft water.

Here's a good CO2 Calculator that is easy to use. Just scroll down, punch in your values and it does the rest.

 

[Shariukas]

Hard water is generally defined as water, which has many diluted ions able to form insoluble compounds. Mg, Ca and several other ions cause permanent hardness of water. KH refers to carbonate hardness. Both form general hardness (GH). The higher the degree (GH or KH), the harder is water. When injecting CO2, pH in soft water falls more than in hard water. Hardness of water acts as pH buffer.

 

[aberg12012]

Hmm... intaresting. I've long understood KH also as "alkalinity" from the reef aquarium hobby. The more "alkaline" the water, the greater the capacity to absorb PH changes. So I definately understand that aspect of KH and GH, being able to "buffer" PH swings... one example being CO2 injection, which has extremely low PH.

So, that being said... pure water, with less disolved metals and other solids is considered "soft?" Does my RO/DI filter (which I use strickly for my reef aquarium) produce soft(er) water than what comes out of my tap? (I measure TDS, which starts at about 200 from the tap, and is 0 after the DI stage.) Or is the water the same hardness no matter what, as you refered to something as permanent hardness? I would assume the RO/DI process strips these properties out of the water?

Don't mean to take my own thread off topic, but I thought it would be intaresting to get some oppinions on this, since it's often confused me.

 

[Shariukas]

Yes, KH is also named alkanity, search the web on these ones, there's tons of info. You understood right about buffering.

RO filter gives very soft water, it reduces both - permanent and carbonate hardness, since it removes ions from water. The term "permanent" means that you cannot remove it by boiling water. In order to remove permanent hardness, ion exchange, precipitating out ions causing hardness or reverse osmosis is mostly used. I don't think that planted FW aquarium needs very pure water, unless tap water is very hard.

 

[echoofformless]

I figured the oxygenation from the bio-wheels and surface agitation wouldn't help the plants any.
Alan

It seems that people so often forget that plants breathe oxygen! This issue always bugs me a bit.

"...the truth of the matter is that green plants breathe in oxygen and breathe out carbon dioxide all the time, both day and night. In addition they use up carbon dioxide and generate oxygen during the day completely separate process know as photosynthesis."

(http://californiawaterscapes.com/FAQPlant.htm)

So you see, increased o2 levels will actually help your plants as much as increased co2.

Aquatic plants have been thriving without human co2 supplementation for billions of years. And recent research is beginning to suggest that surface agitation has little to no effect at all on a plants available co2. If you're supplementing, you're already introducing such unnaturally high levels of the stuff that a good amount is likely to be wasted anyway. After all, plants, like all living things, can only use so much of any given nutrient.

 

[Shariukas]

It's well known about plants respiration process. The point is that when plants get enough light and co2, photosynthesis produces more oxygene, than plant consumes by respiration, so there's no need to aerate water, since plant photosynthesis is the best source of oxygene in a tank.

If you're supplementing, you're already introducing such unnaturally high levels of the stuff that a good amount is likely to be wasted anyway.

Unnaturally high levels of light for plants requires unnaturally high levels of CO2 and ferts Sadly, all high-tech tanks are like this.

 

[reiverix]

Aquatic plants have been thriving without human co2 supplementation for billions of years.

True, but it's hard to compare an enclosed system to a self sustaining environment. Our tanks have no natural turnover of carbon or ferts so we have to provide them ourselves.

And recent research is beginning to suggest that surface agitation has little to no effect at all on a plants available co2.

But available CO2 drops with increased surface agitation, meaning having to inject more into the tank. Seems like a waste.

If you're supplementing, you're already introducing such unnaturally high levels of the stuff that a good amount is likely to be wasted anyway. After all, plants, like all living things, can only use so much of any given nutrient.

Turn up the light. Turn off the CO2. Watch the algae grow. I've been there. CO2 is my friend