I've read these are great systems for aquariums, but they also say they take a lot of the good out of the water as well as the bad, so there was a mention about remineralizing the water (not sure what this is). My house water is very deep alkaline and right now I have to pre-treat the water in gallons before dumping it in the tank for changes. I'm not getting a filter for the tank, I would be getting a system that hooks into one of the sinks in the house. So I was wondering if there was anything I should know about doing this etc.
Thinking about getting an RO system, can you use the water right out of the system?
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RO water is water that has had all the mineral content filtered out. It should have general hardness (GH) and carbonate hardness (KH) of pretty close to zero.
When we talk about water hardness we are generally talking about GH which is how much magnesium and calcium is in the water. So RO with none will be very soft and suit some fish. Fish that prefer hard water wont suit RO water.
A different measure of hardness is KH which is carbonates and bicarbonates. KH keeps your pH stable. Things like carbon dioxide will disolve in the water, and acidify it. KH will prevent this from happening. As RO has no KH it is generally acidic and with no KH there is nothing to stop the pH dropping dramatically even further, which isnt a good thing. KH does some other things too, as its a source of carbon for a lot of the natural processes that go on in aquariums like the nitrogen cycle. So RO water with no KH stops these natural processes from happening.
Remineralising is adding salts to your RO to supply both GH and KH to water that has none. For instance chalk or limestone is calcium carbonate and will increase both GH and KH as it has both the calcium and carbonates. Baking soda is sodium bicarbonate so will only increase the KH. Epsom salt is magnesium sulphate, so will only increase the GH. There are aquarium specific products that allow you raise GH and KH independently of each other and get your RO exactly where you want with regards to pH, GH and KH.
So RO needs remineralising. You need some KH to stablise the pH, and the GH is tailored to the specific fish you are keeping.
Remineralising RO is usually reserved for reefs as tap water contains other chemicals that coral wont tolerate, and the RO process removes these chemicals. Whether you would benefit from RO in a freshwater aquarium really comes down to what your tap water is like and what fish you want to keep. Its really difficult to make hard tapwater soft, but easier to make soft tapwater hard so RO is often used where people have hard tap water, but want to keep soft water fish like discus. RO will take a lot of chemicals and contaminants out of the water, so if you have really poor quality water it might be an idea. You also shouldn't need water conditioner because the RO process will remove the chlorine/ chloramine.
You mention alkaline water, and alkaline water will usually be high GH and KH. If you want to keep fish that like harder water, like livebearers or african cichlids they will probably like your water. If you want to keep fish that prefer softer water like tetras, they would probably benefit from mixing RO with your tap water just to bring levels down a little. If you want to keep discus or other fish that want really soft water, you are then probably in the realm of needing RO with some remineralising. If its a matter of removing contaminants, again remineralising RO is a good way to go.
When we talk about water hardness we are generally talking about GH which is how much magnesium and calcium is in the water. So RO with none will be very soft and suit some fish. Fish that prefer hard water wont suit RO water.
A different measure of hardness is KH which is carbonates and bicarbonates. KH keeps your pH stable. Things like carbon dioxide will disolve in the water, and acidify it. KH will prevent this from happening. As RO has no KH it is generally acidic and with no KH there is nothing to stop the pH dropping dramatically even further, which isnt a good thing. KH does some other things too, as its a source of carbon for a lot of the natural processes that go on in aquariums like the nitrogen cycle. So RO water with no KH stops these natural processes from happening.
Remineralising is adding salts to your RO to supply both GH and KH to water that has none. For instance chalk or limestone is calcium carbonate and will increase both GH and KH as it has both the calcium and carbonates. Baking soda is sodium bicarbonate so will only increase the KH. Epsom salt is magnesium sulphate, so will only increase the GH. There are aquarium specific products that allow you raise GH and KH independently of each other and get your RO exactly where you want with regards to pH, GH and KH.
So RO needs remineralising. You need some KH to stablise the pH, and the GH is tailored to the specific fish you are keeping.
Remineralising RO is usually reserved for reefs as tap water contains other chemicals that coral wont tolerate, and the RO process removes these chemicals. Whether you would benefit from RO in a freshwater aquarium really comes down to what your tap water is like and what fish you want to keep. Its really difficult to make hard tapwater soft, but easier to make soft tapwater hard so RO is often used where people have hard tap water, but want to keep soft water fish like discus. RO will take a lot of chemicals and contaminants out of the water, so if you have really poor quality water it might be an idea. You also shouldn't need water conditioner because the RO process will remove the chlorine/ chloramine.
You mention alkaline water, and alkaline water will usually be high GH and KH. If you want to keep fish that like harder water, like livebearers or african cichlids they will probably like your water. If you want to keep fish that prefer softer water like tetras, they would probably benefit from mixing RO with your tap water just to bring levels down a little. If you want to keep discus or other fish that want really soft water, you are then probably in the realm of needing RO with some remineralising. If its a matter of removing contaminants, again remineralising RO is a good way to go.
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Bit of an edit above.
Are you having any problems?
What parameters for pH, GH and KH is your tap water at.
Going the RO route is going to be an amount of work and money, when just keeping hard water fish is probably path of least resistance. Really depends on how much you want to dedicate to the hobby.
Id get your water hardness tested before making any decisions and then decide what fish you want to keep. Your water company should be able to tell you though, they usually have all their parameters available online, but if not give them a call or send them an email.
Id also consider just seeing how the fish do, and if you do change, make the change gradually.
I keep tetras in pH a little north of 7, my hardness is "moderately hard". The only tetras i struggle with are cardinals, i can keep them alive 12 to 18 months, which is a little less than ideal. Other tetras i have no problems with. My corys thrive.
Id also consider just seeing how the fish do, and if you do change, make the change gradually.
I keep tetras in pH a little north of 7, my hardness is "moderately hard". The only tetras i struggle with are cardinals, i can keep them alive 12 to 18 months, which is a little less than ideal. Other tetras i have no problems with. My corys thrive.
Just to throw an option in the mix. Have you considered collecting rainwater? Its going to be very soft similar to RO.
Ok found some test strips and I did have a high ph test kit, my tap is 7.8 - 8.0 and the water doesn't look to be as hard as I thought, test strips shows between 0-25 which is a bit of a window, I won't have a more accurate number till I get a kit. My main issue for the RO thing is every water change I'm filling about 4-5, 1 gallon jugs and treating them with PH down before adding that to the tank and every time I have to top off tanks same thing.
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One thing you would need to factor in is somewhere to store the RO water your filter makes. RO isnt going to flow out of the filter like out of a tap, it drips out. They typically produce somewhere between 50 and 100 gallons in 24 hours, so you need to have the filter running in advance and collect the water ready to use for your water change.
So this is the one this company is recommending to me, do you think I would need to add anything to this water, or would it be good straight after the RO process?
As said RO isnt healthy to use without remineralising. An option rather than adding salts might be to mix your tap water and RO to bring down the mineral content and pH of your tap water.
At 75 gallons per day, it will take about 3 hours to produce enough water for a 50% water change on one of your 20 gallon aquariums. The standard model has a 3.2 gallon storage, so thats not enough. You can get bigger storage as an optional extra, so I'd go for the 11 gallon storage option so it will store enough water to do one 50% water change. So you wont be able to do both water changes at the same time. If you want to do them both at the same time or ever plan on getting bigger aquariums then id go for the 20 or 40 gallon storage option. This will of course take up space.
At 75 gallons per day, it will take about 3 hours to produce enough water for a 50% water change on one of your 20 gallon aquariums. The standard model has a 3.2 gallon storage, so thats not enough. You can get bigger storage as an optional extra, so I'd go for the 11 gallon storage option so it will store enough water to do one 50% water change. So you wont be able to do both water changes at the same time. If you want to do them both at the same time or ever plan on getting bigger aquariums then id go for the 20 or 40 gallon storage option. This will of course take up space.
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