sirdarksol

But the question becomes whether it is necessary for said health, and if an aquarium is set up carefully, a freshwater tank set up with tap water that is safe for humans shouldn't need RO to remain healthy. My own tap water has a really high pH and I've never had issues with it.
It's usually only when dealing with a saltwater tank that is really susceptible to strange amounts of minerals that RO is necessary. For most freshwater tanks, it's an added expense, not to mention hassle, that does little to help the fish.

(And I disagree that $150 isn't expensive. I can live for two weeks on $150)

pistorta

sirdarksol- Let me clarify, $150 from Home Depot for a General Electric RO unit is a cheap alternative to ones manufactured by aquarium product manufacturers such as Coralife or Kent. It is also a lot cheaper than bottled water, in any form, over time.

I believe that if you do not have the money or are unwilling to spend the money to take care of fish the right way, then these fish should not be kept. No compromises should be made. Fish are a lot more sensitive to water quality than humans. For example, humans can handle chlorinated water supplies whereas fish can not. Yes, fish adapt to different water parameters but within reason. It is very likely these unnatural water parameters (such as high ammonia or pH) will limit the life of the fish through stress. Bottom line, I think all fish keepers should try to imitate the fish's natural water chemistry environment or let the water supply determine the fish kept.

sirdarksol

I agree that there are certain things that should be fixed, but there are very few types of fish that all live in a particular pH. This is why most are so adaptable. The few that are not (African cichlids, for example) live in smaller areas and have adapted to odd conditions. In the end, 8.0 pH isn't really all that odd. If you take pH readings from the lakes and rivers around where I live, you'll get everything from acidic in the vegetation-choked near-swamps in some of the local park systems to 8.5 in the high-mineral, rocky lakes. Yet the types of fish that live in these rivers and streams remain about the same. There are a few divergences, but most of them are due to food or water access (I'm thinking of trout, in particular), rather than pH.
I agree that the ammonia is a potential problem, but it's also a moot point until we have a reading on the ammonia straight from the tap. And if there is an ammonia problem, there are cheaper ways to filter it out than a RO setup and the supplies to keep it running.

I agree that fish keepers should work to imitate the fish's natural water chemistry, but the majority of the fish that we keep naturally live in a wide range of water chemistry. The two biggest constants for most of these fish are waste levels and temperature. The rest changes from lake to lake, river to river, and sometimes even between sections of stream. This is why most fish will adapt, survive, and thrive in a wide range of pH and water hardness.

pistorta

sirdarksol- I'm right, you're wrong.

Just kidding. I agree with everything you said, but...

I often find conflicting resources and am unsure how to interpret them. For example, lets take the neon tetra. Books will tell you that they prefer acidic water (pH <7.0). My LFS owner tells me that his supply is raised in water from the opposite end of the scale (lets say a pH of 8.0). How can this be? Nature does not evolve this quickly. If I were born in 130 degree weather and raised in the same, chances are I would be dead by now. Do you know what I mean? Maybe I'm looking too deeply into things, but if an animal comes from a specific region with specific parameters, I would think this is what the animal has evolved or adapted to survive in. Wouldn't changing these parameters this drastically cause an unnatural strain or stress? Have domestically raised fish changed so much that they are no longer similar to their wild "cousins" in terms of their needs?... I hope I'm not rambling here.

Butterfly

Many of the fish that we get in the LFS are several generations away from their natural habitat and therefore are less sensitive than those wild caught. I commend you for wanting to go that extra mile to make sure your fish have everything they need. It just seems like so much trouble to use RO water,and take all that stuff out of it, and have to turn around and add stuff(minerals etc.) back to it for the health of your fish and plants.
I'm not sure but I believe somebody told me that home RO units take a good while to produce enough water for water changes. Is that true?
carol

susitna-flower

The original post this came from was responding to someone who had high nitrates right out of the tap because they had well water fed from runoff containing high fertilizers content. SO the issue was should someone get an RO filter for tank water, AND household water because high nitrates are unsafe for human consumption also!

What IS our health worth? Personally I think it would be worth the investment. If it were sized properly it could make 25 or 50 gallons a day for the tank, and house water as well (just for drinking and cooking). The filters have to be researched however to get the proper ones to deal with nitrates as well as the minerals. That usually takes a special add on filter.

sirdarksol

Actually, there was a question about ammonia in the water, but the discussion centered around changing the pH, not removing contaminants.
I most definitely agree that, if a water source has contaminants, something should be worked out for all of the inhabitants that are affected by that water source. My family has a water filter (basic AC, I believe) due to the fact that 3M has caused a plastic by-product to taint most of the ground water around here.
However, my statement is that buying an RO system for the sole purpose of changing the pH is unnecessary for most fish. There are, of course, some exceptions, some fish that require a very particular pH. However, most wild fish do not have a tiny slice of the pH scale that they live in. Most of them are capable of easily adapting to quite a wide range of pH.
Your analogy of temperature, pistorta, isn't quite the same. Really, I can't come up with anything that is quite the same. Until it reaches the point where the pH is actually toxic to life (either high or low), the biggest issue that pH causes is making ammonia more toxic. Therefore, if our tanks are running right, and if we don't have them overstocked, and if we're doing regular water changes, a high or low pH won't affect most fish.

By the way, like Butterfly said, there is absolutely nothing wrong with absorbing the extra cost and work of using RO and then "building" the water for your fish. I just don't believe it is a necessity. Sort of like the difference between a planted tank with T5 lighting and a few fertilizer spikes and not much else and a planted tank with MH lighting, a CO2 injector, strictly controlled fertilizer additives, and precisely calibrated mineral quantities meant to stimulate plant growths. The second is definitely better for the plants, but it doesn't mean the first is being negligent.