Reverse Osmosis

Nutrients, fertilization, substrates etc
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eleontie
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Reverse Osmosis

Post by eleontie »

Almost all popular fish/shrimp that I keep has recommend low hardness water, slightly acidic. Arlington water is nothing like that. So I am thinking maybe I should give an RO filter a chance since I can not collect rainwater and such.

Do you have any personal opinions on this ? ex. :
- it is generally worth it ?
- how frequent one needs to change the filters
- how likely is it to mess up the water parameters into an imbalance
- recipe for water changes ( like mix 50/50 or some other percentage )
- get a regular RO filter or one from a pet shop
- will the cheaper ones do ?

Eugen
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halak
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Post by halak »

I have one, so of course it's worth it! :D
I change the filters once a year. I add 1/3 of RO water when changing water; however, I only use it for a couple of my tanks. I got mine at Costco 6+ years ago, and I don't think it's different if you get one at a pet shop.
Viktor
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Cristy Keister
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Post by Cristy Keister »

Eugen, I have an RODI unit that I don't need, if you're looking to buy. I don't know if it needs new stuff in the canisters - maybe. PM me if you're interested.
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Jeff120
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Post by Jeff120 »

I have been thinking about this recently. What has kind of turned me off is the waste water that you get. Also depending on the unit it may take some time to make enough water to do water changes.
Jeff U.

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Cristy Keister
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Post by Cristy Keister »

It does take a while to make the rodi water. You need to make and store the water for a w/c. My unit has a small storage tank. You could also get a float valve to use with the unit and either store the water in a large container or put it right into the aquarium.
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ricoishere
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Post by ricoishere »

I've been thinking about getting one, and have communicated with some SW guys. They all recommend:
http://www.airwaterice.com/c=tOrR9MQSQm ... ategory/1/
Rome wasn't built in a day

I can grow any algae!

:roll:
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ddavila06
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Re: Reverse Osmosis

Post by ddavila06 »

eleontie wrote:Almost all popular fish/shrimp that I keep has recommend low hardness water, slightly acidic. Arlington water is nothing like that. So I am thinking maybe I should give an RO filter a chance since I can not collect rainwater and such.

Do you have any personal opinions on this ? ex. :
- it is generally worth it ?
- how frequent one needs to change the filters
- how likely is it to mess up the water parameters into an imbalance
- recipe for water changes ( like mix 50/50 or some other percentage )
- get a regular RO filter or one from a pet shop
- will the cheaper ones do ?

Eugen
Eugen, im no expert at all but since i mixed one bag of amazonia with eco in my new tank the ph has gone down to an steady 6.4 or so. i haven't tested the hardness but is supposed to lower it also.could be a cheaper alternative, plus im getting some good plant growth :D
Damian Davila
"Fishes-up, chill, Plants too"
"so many plants, so little space!"
JSnyder
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Post by JSnyder »

let me try to answer your questions one by one, I just recently bought a 4 stage spectra-pure unit so I've done a lot of research lately.

Is it worth it?

Well this depends on how much water you'll be making and how much water (and sewage) cost per gal in your area. If you get a standard ro unit the proper rejection rates are anywhere between 4:1 to 6:1. This means for every 1 gal of purified water it makes, it will make anywhere between 4gals to 6 gals of waste water (concentrate). You can use the concentrate for watering plants or washing laundry, although it's uses are limited (it is after all concentrated bad "stuff" from your tap). If your paying for sewage as well as water this becomes costly. I most likely couldn't have justified it's cost at my old house, as I was charged for both water and sewage. I live in a townhouse now where both are covered by the landlord, so it's much more feasible cost wise. (for me :D)

how frequent one needs to change the filters

Every 6 months on the micron pre-filter($20), and the carbon block filter$20). The whole point of these two filters are to protect the RO membrane. The micron pre filter removes sediment that will eventually plug the RO membrane. The carbon block filter removes chlorine that will quickly ruin the RO if it reaches it. The RO membrane itself is the most expensive part usually around $90 for a replacement. If you keep up on the first two filter changes the RO should last about 3yrs conservatively.
All of this is dependent on tap TDS, tap chlorine levels, and general water quality

how likely is it to mess up the water parameters into an imbalance

Very likely, IF YOU USE IT BY ITSELF. Keep in mind this water is extremely pure, it has nothing in it except pure h2o. (no calicium, minerals, metals, chemicals, bacteria, microbes, algae spores, KH, GH, nothing) If used by itself, your animals might die if they don't get the minerals, and elements they need from their food. Aquatic animals are the water around them.

recipe for water changes ( like mix 50/50 or some other percentage )

Generally speaking for shrimp, it's best to mix it with tap water until it effects the overall ph slightly. RO water is acidic due to the lack of hardness and other minerals, your tap is most likely neutral to basic. (so it doesn't dissolve metal pipes and your teeth and such) you want to add enough tap so that the ph of the mix goes up by 1 ph point.

get a regular RO filter or one from a pet shop

Either will do the job, If you want the DI stage you have to go aquarium. If not, either works, just be sure replacement filters are easily available.

will the cheaper ones do ?

Yes, same issue as above. Make sure replacement filters are easily available. Cheaper ones sometimes use non standard sizes that are difficult to source.

I'll leave you with this, you can forgo the entire unit and use aquasoil which does lower kh and ph (I did this for a long time with great success). It has it's downsides, as it's costly, takes a long time to cycle, and doesn't keep it's buffering capacities forever.
Or you get the unit and you can use whatever substrate you choose and make as much water as you need. It also comes at a cost.
Jon Snyder
JSnyder
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Post by JSnyder »

I also had the chance to see the setup of a fairly large CRS breeder here on the East coast, Their tap water is 0-1kh 0-1gh and a low Ph ideal for shrimp. These values are very close to RO. They actually had to add a system to add minerals to their tap water for drinking and so it didn't dissolve their house plumbing.
Jon Snyder
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eleontie
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Post by eleontie »

Thank you for the advice. I live in a condo unit with all utilities included in the condo fee so that is not that much of a factor for me.

I'll let it sit for a while, get advice here and there. no hurry .
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