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View Full Version : RO water use, pH Buffer use, pH crashes, TDS, what the hey?



Xerxes
Thu Jan 12, 2012, 04:14 PM
Lots of posts about pH recently, but didn't want to hijack someone's thread with a question of my own:

1) low KH could cause a pH crash,
2) RO (Reverse Osmosis) water is used to reduce KH so that pH is lowered easier,
3) pH buffers soften water or harden water doing what RO water does, but chemically
4) TDS (Total Dissolved Salts) affect fish health, apparently...

My tap water is 7.0 on the button and I have not been able to get it lower for a breeding tank (pH Down, drift wood, almond leaves use with KH at 3 dH and GH at 6 dH). My breeder/supplier kept my school at 6.0 to 6.5 he said too.

Then one day, my KH is going down to 2 degrees hardness, then 1 dH and my pH drops slowly to 6.0. My discus have a much better color to them and they seem happier.

So, what gives? Is low KH better (the reason I gather people use RO water, but cut it with tap or use Discus salts)? If so, how low. If KH low better, what factors in my tank make it more favorable as this much higher or that much lower in KH?

I gather that there is a KH sweet spot so that pH is lowered easily but does not crash? Btw, I am about to get a RO filter. What am I looking for or what make is best for us fish people?

I know, I ask a LOT of questions. :roll:

ILLUSN
Thu Jan 12, 2012, 10:33 PM
KH IS A MEASURE OF THE AMMOUNT OF DISOLVED CARBONATE IN THE WATER.

some buffers use acids to split CO3 into CO2 (and H2O)
as kh drops so does pH, as CO3 is converted to CO2 (and H20 and carbonic acid) tds will drop, this drop in tds softens the water, wood absorbs CO3 and also softens the water s well as releasing tannins and humeric acids that lower ph.

alow kh leaves yo open to a ph crash, with ultra soft water (kh below 3 degrees) keep EVERYTHIG clean, any build up of organic matter will push equilibrium towards the production of nitric acid and a pH crash.

aim for 3-5 degress kH.

Ro kinda a waste of money, not just power but it takes 10-100L of tap water to make 1L of RO water.

BobbyBruce
Thu Jan 12, 2012, 10:45 PM
Hi Xerxes,

I have been using RO water for a number of years and using Kent Marine RO Right to adjust to my requirements.

As Illusion has mentioned you will have waste water when producing RO water, mine goes onto the garden so is not a total waste. Modern RO units are now operating at approx 1:1 RO Water/Grey water. If you are looking for some good systems try here http://www.psifilters.com.au/ While based in Tasmania they provide very good service and Peter (?) has had a lot of experience with discus.

Good Luck,

Bob

Xerxes
Fri Jan 13, 2012, 09:27 AM
KH IS A MEASURE OF THE AMMOUNT OF DISOLVED CARBONATE IN THE WATER.

some buffers use acids to split CO3 into CO2 (and H2O)
as kh drops so does pH, as CO3 is converted to CO2 (and H20 and carbonic acid) tds will drop, this drop in tds softens the water, wood absorbs CO3 and also softens the water s well as releasing tannins and humeric acids that lower ph.

alow kh leaves yo open to a ph crash, with ultra soft water (kh below 3 degrees) keep EVERYTHIG clean, any build up of organic matter will push equilibrium towards the production of nitric acid and a pH crash.

aim for 3-5 degress kH.

Ro kinda a waste of money, not just power but it takes 10-100L of tap water to make 1L of RO water.

So, ILLUSN, you use pH buffers? Which are good? Not necessarily brands, but the chemical composition is fine too. I'm kinda worried about byproducts being bad, but carbonic acid is soda water!! I'm guessing its not much produced? What concentrations are we talking about here (ppm or molarity or whatever quantitative measure is fine as long as it is quantative). A link to an existing post or web site is great too.

Xerxes
Fri Jan 13, 2012, 09:31 AM
So, ILLUSN, you use pH buffers? Which are good? Not necessarily brands, but the chemical composition is fine too. I'm kinda worried about byproducts being bad, but carbonic acid is soda water!! I'm guessing its not much produced? What concentrations are we talking about here (ppm or molarity or whatever quantitative measure is fine as long as it is quantative). A link to an existing post or web site is great too.

Ok, I just saw in the other post, "Best pH buffer?" (http://www.discusforums.com/forum/viewtopic.php?t=23380) that the best recommended there is
Discus Buffer by Seachem.

ILLUSN
Fri Jan 13, 2012, 11:49 AM
Depends on what you want the buffer to do. Discus buffer is good but don't use it in a planted tank. Acid buffer is good but more expensive and can be used in planted tanks. Both buffers use salts ( metallic cations) and will increase your tds. HCl will lower your ph and drop your kh. It's also cheap and has less of an effect on your tds

Xerxes
Sat Jan 14, 2012, 06:43 AM
Depends on what you want the buffer to do. Discus buffer is good but don't use it in a planted tank. Acid buffer is good but more expensive and can be used in planted tanks. Both buffers use salts ( metallic cations) and will increase your tds. HCl will lower your ph and drop your kh. It's also cheap and has less of an effect on your tds

I read somewhere else here (I can't remember the post to cite it) that many institutional breeders use HCl and the poster said that hobbyists with huge tanks should do the same, but cautioned that it's dangerous and should be used with great care.

I get that, but why couldn't the average joe hobbyist just drop the HCl in an aging water reservoir tank, monitor until desired KH and tds and pH are reached (and so as not to shock the fish with too much of a difference in such numbers with the existing discus fish water chemistry) then proceed with the water change? No danger, best all around benefits.

That seems MUCH cheaper and even simpler than using RO water, and doesn't have the unwanted byproducts of buffers. People seem to age their water in a holding reservoir pretty much anyway. Since everybody isn't up and running out to do this (as far as I can tell), I figure that there's some catch? If so, please tell. I'm asking because I can't see the catch.

(I read somewhere else that people were having a hard time getting pure ammonia to do a fishless cycle, post 9-11 restrictions on available chemicals. Well, I was wondering just that I know of a plentiful supply of household ammonia. Actually, it's less household and more body-hold) (Before you turn your nose, literally, I actually cycled my breeder tank using this...source. If you're really grossed out by it like I was at first, you can do a major water change with the seeded biofilter, or sponge one, once the cycle is finished but before you add the fish).

scoob
Sat Jan 14, 2012, 08:22 AM
HCL will drop the PH but to soften hard water you will need to filter with peat or RO machine.

Hooked
Sat Jan 14, 2012, 10:16 AM
Hi Xerxes,
I don't really think there's a catch to people not using HCL. (maybe the thought of what the acid is capable of doing to cement, metals etc and the potential of harm to our beloved fish or ourselves if handled incorrectly) Just maybe its not really been common knowledge or had the benefits explained recently like not adding to the total dissolved solids etc. The info that comes out in the threads like this one you started is great for spreading the word and I for one will definitely be looking into it.
I looked up Hydrochloric acid on Wikipedia and this is a snippet of what the good people there had to say,

quote - pH Control and neutralization:
Hydrochloric acid can be used to regulate the acidity (pH) of solutions.
OH− + HCl → H2O + Cl−
In industry demanding purity (food, pharmaceutical, drinking water), high-quality hydrochloric acid is used to control the pH of process water streams. -unquote

Cheers

Hi ILLUSN,
have you found any particular source or brand that you would recommend over others? Also I know its a hard question to ask as all our water is different but "roughly" how many mls per 100lts or unit measure are you using to adjust your water. This will give me a rough idea of what to start with. I'm investing in a rain water type holding tank soon to age my water as a couple of plastic 44's are not keeping up any more so this is a great tip.

Cheers

Cheers

Xerxes
Sun Jan 15, 2012, 09:33 AM
Kind words, Hooked.

Another question, however: What the hey, does TDS (Total Dissolved Solids) have anything to do with fishies keeping? Affects gas exchange in the gills for the fish? I read about a lot of stuff but not so much about TDS. (I did see that some vendors do sell a TDS meter).

Thanks in advance.

ILLUSN
Sun Jan 15, 2012, 10:32 PM
google harder for your answer to TDS, it is important but you can get fish used to a diffrent TDS

i use 5-6ml of HCL in 220L of sydney water (prospect res) this gives me a ph of 6.0-6.6.

i use the bunnings brand HCl

Nev
Sun Jan 15, 2012, 11:27 PM
Here's a good link that explains tds, gh and relationship to water quality etc.
http://www.sydneycichlid.com/aquarium-hardness.htm

Xerxes
Tue Jan 17, 2012, 04:42 AM
So, TDS is not as important as the kH and gH breakdown? That's what I got from the article, but just wanted to get my homework checked. :wink:

This raises another question: Is it possible to have optimal or decent kH and gH levels and still have a TDS level that is too high or too low? I mean, is it possible that I can check for kH and gH and miss dangers to discus (or fish in general) because of dangerous TDS concentrations? :shock:

I am exceedingly grateful for all of your collective experiences and willingness to reply to my noob and boob questions. :D

Hooked
Tue Jan 17, 2012, 05:16 AM
Hi guys,

good answers and info given that I will gratefully use also,

likewise, big thanks! : )

Cheers

Xerxes
Tue Jan 17, 2012, 05:37 AM
Ok, found my own answer about TDS overall and how it affects fish here (http://www.tdsmeter.com/what-is?id=0005).

The site doesn't seem to be written by an authority on fish, but rather on chemistry in general, however.

Nev
Tue Jan 17, 2012, 10:59 AM
Don't get too hung up on water parameters, as long as its not extreme one way or the other the fish won't care. Just get your ph somewhere between 6 and 7 and they'll be fine.
I'd only worry about it if l had genuine wild caught fish and heckels at that.

Xerxes
Tue Jan 17, 2012, 04:04 PM
Don't get too hung up on water parameters, as long as its not extreme one way or the other the fish won't care. Just get your ph somewhere between 6 and 7 and they'll be fine.
I'd only worry about it if l had genuine wild caught fish and heckels at that.

That's helpful too, actually. The way people were talking about TDS, I thought it was the IT water parameter.

Hooked
Tue Jan 17, 2012, 06:24 PM
Hi Xerxes,

I couldn't tell you what the total dissolved solids count is (in parts per million) of my local town water. I just know you don't want it to high.
Basically I treat with a dechlorinator, 50mls of Supachlor for a 220lt drum of water. Add 2-3 teaspoons of Seachem acid buffer (going to try HCl when the Seachem runs out) to the drum to get my water to about 6.5-6.8 and leave a small air pump running an air stone in it to circulate the water. The best tip I've had was not to fuss to much but be consistent. Oh and I've tested for hardness once or twice. Its not super soft, just a tad harder than is usually recommended.
I started building a picture in my head, earlier on, that my water must have been full of all sorts of unwanted stuff.... Then after being consistent for a couple of months (whilst searching for an R.O unit!), regular changes with same ph, things started to happen. Fish started laying and I came to the conclusion that it cant be as "bad" as I thought.
My lfs tells me some breeders in Asia grow there fish out in concrete tanks which contributes to some fish getting use to being in more Alkaline water?
You can also get into testing the conductivity of your water (I bet a lot don't).
I'm sure the more you tweak your water the happier they possibly get, better colours, better feeding, growth etc, maybe better breeding?
I find my ph is the best tool. I keep my display around 6.8-7.0, but if I lower it into the low "6ish", its enough with a water change or two to get most of them "shimmying" all over the place. A low ph in the breeding tank produces a better slime coat as well for the fry to feed on apparently.

I'd say try what you have at hand. Probably a good idea to check for how hard the water is (hopefully not to hard) and see what happens after a couple of months of consistency. Then maybe a drop in ph. The fish will let you know by there behaviour, colours etc, if they are not happy, I'm told.

I'm a newbie too and think I was where you are at not that long ago. I got to the point after a lot of research where I understood Kh, Gh, TDS, Conductivity, R.O, De-ionisation etc etc a few months back. But ask me to explain it ALL to you now and I couldn't....... If my fry don't grow very well then maybe I'll get you to explain it to me again : )

All the best,

Cheers

Xerxes
Tue Jan 17, 2012, 06:59 PM
I guess I'm fussing because I had orange pigeon blood mating pair laying eggs a few times but almost all of the clutch died by turning white. I tried everything: anti-fungal medication, kept them really private like when they were romancing the stone (actually the drift wood), goodly frequency of water changes but not at great volumes/percentages of total...

One, I kid you not, one did get to free swimming, so they were not two females, or maybe the male didn't know what he was doing (or maybe he wasn't doing it well...).

I didn't even get to the gill flukes being the problem at a couple of weeks in, since they never made it that far. My new golden snakeskin discus are about at the size to start breeding from the juveniles I bought them at, and I think they have (although they are strangely very friendly and communal, even though I could have sworn there were residual egg remains from when the evil hoarde had eaten them. But, they're not territorial yet, the breeding pair, so I'm not really sure if they're breeding (I have them under surveillance with a Skype camera on them so that I can see them from work from my iPhone with the tank cam on auto receive of in-coming calls--there was cool way to do that explained in a web site). They're doing the bowing (although no shaking yet), and they're pecking at some surfaces. Maybe they didn't breed yet. Anyway, wanted my golden snakeskin to get it right without their noob keeper flubbing it all.

Getting good growth though and haven't killed any one of my newest batch (unlike the train wreck keeper mistakes I had with the first batch I started with).

Anyway, thanks to all for the very helpful advice. This thread really answered all the questions I could have on this one aspect of discus fish keeping anyway.