View Full Version : INFO ON CHANGING pH!

01-18-2003, 11:06 PM
For anyone looking for info on modifying pH Values and discus please read this thread:



01-19-2003, 12:35 AM
Great post Randall. I couldn't have said it better.

01-29-2003, 07:09 PM
extremely good advice!

*pat Randal on the shoulder*


02-02-2003, 05:27 PM
Good Thread ... thats how it should be ... just keep consitant water parameters and as long as they are not extreme then things should be OK. 8)

02-26-2003, 07:30 PM

cool stuff


03-10-2003, 02:50 PM
As they say, "If it ain't broke Leave it alone".


03-22-2003, 09:59 PM
glad I read that, my first pair just spawned for the first time, of course if was in the group tank so the eggs didn't survive. I'm planning on mixing RO 50/50 with tap at my TDS is off the scale in the tap water. May have to play (in a glass) to get the correct percent to the the TDS down. Whats a good safe number there?

03-23-2003, 07:30 AM
Thanks for the advise - I'm planning to start with discus and the water treatment seemed somewhat daunting !

A question though : should tap water go directly from the faucet to the tank, or should you add something to take out chemicals, or age it for the same reason ?


03-23-2003, 06:55 PM
most people have the breeders water under 100 ppm tds.

I always "age" my water in a barrel to off gas CO2 and let the pH stabilize. Age means to heat and circulate or agitate the water. Harder water needs stronger agitation and/or more time to stabilize.

With soft water a simple airstone in a 55 gallon drum overnight will do the trick. I can stabilize the pH of my GH 11, TDS 176 ppm well water in three hours with heavy agitation through a pond pump. It takes days and days to stabilize with just an airstone.

If I had chlorine I would also add a dechlor product.

04-16-2003, 10:22 PM
Hey, thanks, but ...

Thanks, cause that thread answered about half my pH buffer question - I swear it wasn't here when I started that thread. I'll be experiment'n with peat <smile>.

But, about that thread. There are two reasons I think it might be very, very misleading to newbies like me. I note that the successful breeders drop the pH for their breeders. And, the folks that aren't dropping their pH for the breeders get plenty of spawns, but no success.

I've been reading for about 4 days now (hey, no fish, so ...), so I apologize for not providing a reliable reference and I'm quite prepared to be poked fun at, so here goes:

My still developing take on water chemistry suggests that there is very likely a correlation between hatch rate and pH. We know that the Discus fan the eggs to make sure there is a good water flow. And, most folks assume this is an oxygen supply issue. I believe there is more to it than oxygen. Discus lay eggs designed to survive an acidic environment. So, I'm hypothesizing that much like the slime coat that disappears as the water becomes more basic (I hate using alkalinity because that means KH which supports pH stability). Well, both types of water interact with whatever is in that water, but basic solutions leave atoms behind, while acidic solutions strip atoms from whatever they interact with.

So, I'm suggesting that the eggs need the acidic solution so that their outer membranes don't get tough or clogged by their interaction with a basic water environment. I'm also suggesting that the potential parents need the acidic solution to support the production of a good, healthy slime coat. If this is correct, it makes sense for the Discus to abandon their efforts when they lack a well developed slime coat - who among you would deliberately have children you weren't prepared to nourish? And, I believe Discus (like everything else) are motivated to reproduce, and many are likely spawning in these poor hatching conditions based on this drive, combined with a healthy dose of optimism - that is, I think they are hoping that the water changes signal the start of their rainy season where the water will become more acidic and hospitable to their reproduction.

I do have a little support for the idea that breeding is more successful in the acidic environment - check the Lucanus article in the Aquarium USA 2003 Annual. He suggests pH 6.0 to 6.8, 86 deg F, and soft water for breeding, but elswhere concedes that "most" Discus will thrive in medium hard, neutral pH water even if 6 - 6.5, soft water is ideal.

In 4 days, the best explanation I have found offered for this "ideal" condition is matching their natural biotope. That is a good reason, but I like to dig deeper so that I can understand why this makes a difference. My degrees are in business, but science has always been a hobby of mine, so I guess that drives my need to understand why. Also, I really hope that making the effort to understand both water chemistry and the Discus profile will give me a handle on the degrees of freedom that exist when try'n to keep them happy and productive.

Oh, and one reason I can think of that you might need to just move to the "ideal" came up this afternoon. Went by a lfs and saw that they'd picked up a few discus (I understand it was a lot, but a few by the time I saw, and I was only there 4 days ago - LOL). Well, scribbled right on the side of the cardinal tetra tank (also new arrivals) was the demand that you bring a water sample before they'd sell the fish (I cheered). First the lfs has shown itself responsible enough to put fish welfare ahead of profit (unusual in my experience), and they were keeping all of their Amazon region fish in biotypical environments (cheered again, 'cause this was the first time I'd found this at a local lfs). Did I mention that I met the Discus keeping employee <LOL>.

So, if there are other newbies like me who look forward to viewing the entire Discus life cycle some day, I think the ignore your water issues suggestion is very dangerous. Some will get lucky and serendipity will play a hand in providing water that just works. Others will likely get to watch their fish on a lot more trial runs, but drop their chance of succeding.

So if you had the stamina to read my ramblings - please, please tear them apart. Particularly if you are getting a full breeding cycle in basic water. Even more particularly if you are getting success in pH 8.2 type basic water. By success I mean viable healthy fry that grow to health adults - for this discussion, I'd view a spawn as only a partial success. I don't have the fish (gotta practice applying my developing water chemistry expertise <LOL>), but my plan is to put them in a biotypical environment so that I can treat all my water together. Yeah, I'm gonna automate it (just water changes, filtration will be unique to each environment), so mixing up special water for breeders isn't appealing to me (with luck breeders could easily become more than 60% of my water demand, so ... I like the one system idea. That way, I can just up the temp a bit in the breeder tanks, and up the water turnover radically when it's time to simulate the rainy season (every creature deserves a spring break <smiles>).


04-17-2003, 08:55 AM
O k so you dont have to change the ph if your ph is a little high,but can someone answer me this.Does a high ph not let for the fish to grow its full potential.Personaly i have seen small babies grow out from my tap water and im at 7.4-7.6 ph.But my young adults dont seem to be growing much ,maybe its just me since i see them everyday i wouldnt really notice growth. ???

04-17-2003, 02:12 PM
Mine grow nice and big in 7.8 pH. I think Cary's pH is 7.6 (Great Lakes Discus). The secret to growth is lots of clean water of the same steady parameters.

04-18-2003, 01:22 AM
Please allow me through in my two cents.

Back in my early days of raising Discus, I used Discus Buffer, PH down, PH up and many more. None produced good results. My entire Discus collections were stressed out. Some even committed suicide by banging their head on the glass wall. Now days I donít use anything but my PH are just fine (5.5-6.5). Here is my secret: keep it simple and be patient. Discus is fish. Your aquarium is a nature water pond. Let the nature take charge and you, my friend, just relax and observe the fish.

If PH is 5.5 - 8.5, donít change water or filter media as long as the fish still feed normal (no leftovers).

If PH is below 5.5 and dropping to 5, change 15% water. If PH bounced back for more then 24 hours, you got it. If PH dropped again, change more water or slightly wash your filter media.

I have been doing that for the last 4 years in both 300 ppm hard water or 120 RO mixing water. The only difference is that the soft water needs more monitoring than the hard water.

Forgive me if my two cents generates more confusion.


04-18-2003, 01:41 AM
You missed my whole point here.

I'm not talking about setting up a breeding program or successfully breeding discus. That's a whole other kettle of worms (CBW?). I'm talking about raising discus from the 2-3" fish that most people buy. A novice breeder can get all the facts and opinions about pH modification and the necessity in the Breeding section. All I meant with these threads is that almost all drinking water conditions in the US can be used for growing out and keeping discus. Another point was that consistant water quality is probably the most important thing in discus keeping. Attempts to modify pH because someone "Knowledgeable" told you your water has to be 6.8 frequently have deadly results for the newbie discus keeper. Better to keep them at 8.0 than try to modify to 6.8 or lower with chemicals bouncing the levels all over creation.

I hope I didn't sound too harsh here, that's not my intent or the intent of anyone on the board. You need not be worried about "being poked fun at" or "ripped apart" There are plenty of forums that will do that, but this ain't one of them. Last but not least, I personally know a Major US discus breeder that keeps all his tanks at 7.2......


04-18-2003, 02:13 AM
I have to agree with Randal on keeping the water consistant, When I first got in to Discus, yes the Fish store told me the same thing, get your Ph down, well needless to say my fish died. $400.00 worth!!!!! Of course the internet was not available back then and this forum of very knowledgable people wasnt here to help me even though I lurk most of the time.

04-18-2003, 05:00 PM
Oops <smile>,

Randall, you are absolutely correct. I did miss the point on my first read. Then I read it a couple more times <smile>. But, to be honest, I think that's why I spoke up.

I type to fast to be eloquent without writing it out longhand first - not likely online <laughing>. But, you'll find (since I'm about knee deep here already), that I like to stir the pot and participate in discussion. I learn much faster that way, and I hope it doesn't appear too selfish.

But, I'm almost sure I altered my setup plan the same night I posted to this thread. The discus won't get biotypical water for their developmental stages if I get lucky enough. Nope, they get the modern equivalent of chewable flinstone vitamins instead (my analogy for more nutrient rich water). And, <fat smile>, as of this morning, I can replicate pH in the 7s without chemical additives (and that is my target for developmental a stable pH in the 7s stripping as few nutrients as possible) - time will tell me how stable it is.

Randall, didn't sound or feel harsh at all. Exactly the response I wanted - and even expected by the time the post had sat for a few minutes. I guess I suggested the ripp'n stuff 'cause I just wanted y'all to know I accept my neophyte status, so I place learning way over any attempt to appear "correct", but I know that this isn't always obvious based on my communication style, so ... Most of the time my questions come out like thoughts (at least to the degree that my ramblings might be qualify as thoughts <smile>).


05-24-2003, 10:37 AM

Water pH does not impact fertility and fanning of the eggs do not effect acidity.

Alkaline water are typically high in calcium and magnesium. Calcium ions effect membrane fluidity and high calcium concentrations will hinder sperm penetration. pH, which reflects hydrogen ion concentration in the water, is not a significant factor. RO significantly reduces calcium so that breeders are often kept in RO water. Note that a local guy breeds his discus in straight tap water at 600 uSi, so hardness is not necessarily a barrier to success.

The key is to maintain constant water conditions. The way to do this is to NOT MESS WITH THE WATER. Your water comes from a reservoir with millions, probably billions, of gallons of water. So if you don't try to change water chemistry, then the water quality will be constant. Discus value consistent clean water quality much more than specific pH or hardness. In fact, isn't this true of all fish?


08-21-2003, 09:36 PM
Keeping things simple always seem to work out better then when we/you/them try to over anyalse something that in all honesty does not have a lot of scientific evidence to support.

Creatures (generally) adjust to their environments within reasonable limits. No one is going to duplicate a river, lake, or ocean in their home (OK, maybe Bill Gates). Most of the mistakes come from trying to do exactly that (add this, subtract that, etc., etc.). Some people are just too anal to appreciate what does not have to be done to keep creatures (I know Discus are special. . . come on now, what isn't).

Think about it ::)

Tom-ee G-ee
08-22-2003, 12:49 PM
I'd like to say two things if i may...

Firstly i'd like to shake hands with Milton, for all the reading up, asking around and thinking you have done on the post you have written. I really must congratualte you, not many people are that dedicated. In a way i agree with you and i think your hypothesis is a well thought out one and i follow what your saying. Keep it up great post... great read...

Secondly i would like to say that my water out of the tank is quite high up on the scale. Fair enough keeping the PH constant and water changing often, but witha PH of about 8, in my 75 litre tank isn't that a bit tooo far up? Isn't lowering the PH from that level almost mandatory (lol)?

I am placing peat into my trickle filter and seeing if that can at least bring it down naturally to a stable
ph thats at least marginally better than 8.... i also have a marine tank and the tank water is great to fresh water top ups from evapouration and it's kind-of hard to comprehend keeping discus (which quite obviously are not marine fish) in the same water with ph used in that of a marine evironment....

Comment would be greatly appreciated..

Thank you in advance,