Just r/o or r/o+DI???

[falcon]

I am a bit confused at the moment. Can someone please explain to me what each will do to water chemistry and which to use for planted tanks and altum tanks.

I usually mix about 45% of r/o DI water to 55% tap at w/c.

Thank you.

 

[Darkblade48]

If you were to use pure RO water, the water would be lacking in minerals and other trace elements that could be provided at w/c. However, your current w/c plans (mixing RO water with tap water) is fine.

If you were to use pure RO water, I'd assume that the water would get really soft, and plants wouldn't really survive unless you were dosing all the stuff the RO filter was taking out.

 

[MasterBlaster]

But, pure RO is cool for a fish only tank, right?

 

[happychem]

Using RO water seems foolish to me, unless there's an existing problem with tap that makes keeping your tank balanced extremely difficult, you're breeding a soft water (low TDS) fish, or you're keeping a touchy fish that requires it. Although I'm still not sold on the need in the last case, nature doesn't provide RO water?

There's nothing wrong with using it in any case, my only question to you would be why? It's really something that you have to answer to yourself, not me or anyone here.

What I mean is: before I get anything to add to my tank or change, I ask myself why I need it, is it necessary and is it the best solution to the problem, if there is one? (this applies to all facets of life as well )

If I can justify to myself the necessity for something, being truly honest with myself, then I'll do whatever is necessary to obtain it, like save up for a couple months or whatever. If not and it's just a passing desire that won't improve the situation in the tank, then I'll save my money for something else.

 

[Darkblade48]

But, pure RO is cool for a fish only tank, right?

As happychem aptly put it, most fish don't need RO water, unless they are really picky about TDS or the water quality (discus come to mind). However, using RO water isn't necessarily a bad thing (well, other than the fact your wallets takes a hit )

 

[happychem]

And it's a tremendous waste of water, the degree depending on the rejection ratio (amount of TDS enhanced water rejected vs. amount of RO water produced).

 

[falcon]

Sorry, I don't think my question got answered. What is the difference between r/o and r/o+DI? I'm concerned about gH/kH/pH. I think DI will remove most if not all of gH&kH where just plain r/o will maintain certain levels? Right or wrong?

Using tap water for most fish is fine. But, there are some soft water fish and wild fish that would benefit by addition of r/o water to make it softer, for one thing. I am adding r/o water to my altum angel tank as I don't think keeping them at tap water is an option. I can reduce my pH with co2 injection, but softness is one thing that r/o water is good for. I also have another tank that I have some wild fish in as well, bosemani rainbows, congo tetras, clown loaches, to name a few. I have also been trying to keep some discus as well. It hasn't been going to well and I wonder if I had used some r/o water to soften the water whether that would've helped. This would mostly apply to wilds.

falcon

 

[got_nailed]

RO and RO+D

This will be a bad way to answer it but there is the $$$ and there is one more filter on it. Do not quote this but RO will get out about 90% and the RO+D gets out 98% of the stuff.

And yes use some RO water in your tanks will help out with the fish you have. I would start at 40% RO and 60% tap and see form there.

But I think the QU needs to be what type of fish, plants do you want to keep. And you need to get a good look into to your water as in test for PH, KH, GH, ammonia, nitrites, nitrates, phosphates, and the list can keep going on.

I know I didn’t do to good but that’s a good try. For some of the best info on that type of filter go to a good salt water shop near you.

 

[justinb013]

How much RO is needed in relation to tap water for your angels, etc. would also depend a good bit on the condition of your aged tap water. The water here is so soft that I could almost get away with using tap to keep wild angels, breeding apistos, etc. I actually DO use just plain ol' tap in my ram tank, and they are happy enough to spawn.

Sorry, I'm not much help when it comes to RO vs. RO+DI.

 

[plantbrain]

DI= deionized, so it'll remove any ions and give you basically a pH of 7 water. RO may have a few more ions in there.

If this is for fish, using the RO is fine.
Blend the tap with a % of RO till you get a KH of 3 and a GH of about 5.

Thias works well fro Altums, Discus etc.
You can knock the KH to 1-2 for Apistos or to induce breeding.

Otherwise, keep it in that range relatively.

Regards,
Tom Barr