Ro Water Issues

[Charis]

I'm trying to get set up for shrimp keeping and I'm having trouble with my water parameters.

I thought that RO water would be the solution to these issues, but perhaps not. I've just set up my new RO system and the TDS of my RO water is around 28 and the pH is still well above 7.6. That's as high as my test kit will check and I haven't got my pH meter calibrated with distilled water yet. Can I expect better than this? What is your experience with the end pH of RO water using Calgary as a base source? I literally just set this system up, so perhaps some time will change the parameters as the instructions said to make 30G of water before aquarium use.

If the pH of RO water is still so high, how do I manage shrimp? I thought this would give me a huge jump on having to use peet or pH impacting substrates. I do have an DI unit coming to add onto this, but does any one have an idea of how this will alter the parameters?

Thanks so much!

[Charis]

Ok, false alarm. My TDS is already down to 8 and the pH is now 6.4, so I can't complain about that. It must just be the "breaking in" of the filter that was giving me higher readings. But, I'd still love others input on their systems and expectations.

Also, when they say the membrane must stay wet, how do I do that? I only plan on using this a couple times a week. Does it dry out in-between?

Thanks!

[Ron]

RO/DI water should have a TDS of 0 ppm.

To keep the membrane from drying out, I would just add valves to the waste water line and produced water lines to trap water in while it's not in use.

What kind of shrimp are you preparing for? You still may need an active soil to maintain a low pH, water with a very low KH is very unstable and you can get huge pH swings unless it's being buffered by an active soil.

[jumpsmasher]

My RO water is around 6.4, TDS like Ron said should be 0ppm

I flush out the RO filter for a good 10-15 minutes or so whenever I change filters so probably a good idea for a new system as well. Than I let it run for about a couple of hours - I don't use that initial batch of water for my tanks (or for drinking) - treat it as waste water essentially.

Like Ron, I have a shutoff valve on both ends. I usually just shut it off on the outlet end first while it is running. than shut off the valve (and water) on the inlet side.

[Charis]

Thank you! The valves in the lines are a great idea! I guess you can just find something like that at Home Depot? I'm starting to feel like I live in the their tubing section....

I'm trying to get setup for both neos and caridinas. On that note, do you find it necessary to alter our tap water with RO for the neos? I'm aware that their preference is a pH that's a bit lower than ours, but will they actually do fine and reproduce without altering the water parameters?

Clearly the caridinas need the RO water. If I was to get some sort of a buffering substrate that will keep the pH lower, is there anything cheaper than the amazonia?

[Ron]

I usually get my John Guest valves at Lowes but I'm sure HD will have them as well.

I used to mix RO and de-chlorinated tap water for neos, worked fine but you need to keep track of tap water TDS. Neos can adjust to a wide range of water paramaters, just takes time.

Amazonia is about as cheap as it get's per liter. If you don't need a 9 L bag, some of the other brands may be cheaper. Go check out SKA Shrimps for all your supplies, bag of Amazonia is $40.

[Charis]

Thanks for the advice! Is John Guest the name brand? Or the type of valve?

I'll have to think more about the substrate. If the RO and remineralization has put given the correct parameters, are the buffering substrates necessary to keep the numbers down? If you don't have these does the pH and TDS go back up?

[ckmullin]

Thanks for the advice! Is John Guest the name brand? Or the type of valve?

https://www.google.ca/search?q=John+Guest+valves

...type of.

[Charis]

Ah yes! Look at those little guys! Thanks for the link… it's good to have a visual.

[ckmullin]

No worries. Dunno what these guys have for that type of valve but I've gotten assorted tidbits from these guys before. https://www.amresupply.com/locations/calgary

[jumpsmasher]

Thanks for the advice! Is John Guest the name brand? Or the type of valve?

I'll have to think more about the substrate. If the RO and remineralization has put given the correct parameters, are the buffering substrates necessary to keep the numbers down? If you don't have these does the pH and TDS go back up?

The generic term is push-to-connect fittings. John Guest is the brand while the product line is called SpeedFit and it is by far the most common one used by installers.

I actually prefer Parker's LIQUIfit push-to-connect fittings over John Guest but both are very good but expect to spend a premium over generic fittings you find on eBay etc;

I buy mine from US Plastics but you can probably find it locally if you only need one or two.

The main reason you want a buffering substrate is like Ron mentioned, the idea water perimeters for shrimps has a very low KH (0-1) so it will be proned to pH swings due to things like Aeration, water change or anything else that is in the tank.

I.e when I used my RODI water for with some gravel / substrate I know the PH will jump to 7.5 even though the water going in is at 6.4.

It certainty can be done without a buffer substrate but you will have to constantly monitor your pH and watch everything you put in the water.

For me, the substrate is the easiest way to control the pH and keep it stable. Whether it is ADA aquasoil for low pH or natural gravel for neutral pH or argonite / crushed coral for high pH.

RO water started you off on a "blank slate" after that it is up to whatever is in your tank to buffer the PH and the substrate plays a big role in that.

[Ron]

Thanks for the advice! Is John Guest the name brand? Or the type of valve?

I'll have to think more about the substrate. If the RO and remineralization has put given the correct parameters, are the buffering substrates necessary to keep the numbers down? If you don't have these does the pH and TDS go back up?

For your neos you can go with an inert substrate and a remineralizer that adds more KH to keep pH stable. For your low pH tanks an active soil is just about necessary unless you want to have a pH monitor/controller. The shrimp won't like the pH swings and depending on what shrimp you are planning to keep, a bag of active soil might only be the equivalent cost of one or two shrimp.

[Charis]

Ah yes, the cost! Very true when you point out it really is the cost of only a few shrimp…. and if it prevents them from dieing AND simplifies everything, why am I resisting! Excellent points made and I think I'll get some amazonia.

In regards to the fittings, there is an intake and two outputs on my RO unit. Do you need a valve for all three of these? Or just the intake?

Thank you everyone, I really appreciate the information.

[Ron]

I would definitely have valves on the outputs, they're the closest to the membrane. If you don't want to have one on the input, you could probably get away with it but for the $5, I'd have one on there too.

[Charis]

I'll do that! Pretty minimal investment compared to the membrane… finding time to go to the hardware store is another issue! It will happen, though!