ph variation tolerance

[champak]

how much ph and tds variation can discus fish tolerate during water changes?

[Eddie]

how much ph and tds variation can discus fish tolerate during water changes?

Not sure about TDS but generally .2 is as much as I'd sway in PH. Also, swaying up .2 will have a less negative affect on the fish, less stress.

Eddie

[champak]

is bio load responsible for ph swing? or its because of carbondioxide liberated by fish?

[Eddie]

is bio load responsible for ph swing? or its because of carbondioxide liberated by fish?

KH is generally what controls PH stability. Co2 can affect PH also when it is gassed off in the aquarium through water movement and aeration. This is why aging water stabilizes PH, most of the time, depending on your source water. Nitrification in itself will reduce the KH of water in the aquarium. There are several things that can affect the PH but the KH is what matters most IMO.

I am far from an expert in the water field, just an expert at changing alot of it! LOL

Eddie

[champak]

my ph swings 0.3 after water change do i need to worry?
I age my water for 24 hours and dechlorinate during water change.
Water changes are daily 90%.
my tds is 230 ppm
ph after aging 8.4
i dont think at 230 ppm my kh will be low, never tested kh and gh.
Can crushed coral could control the 0.3 ph variation? donno how would crushed corals raise tds in relation.

[Eddie]

my ph swings 0.3 after water change do i need to worry?
I age my water for 24 hours and dechlorinate during water change.
Water changes are daily 90%.
my tds is 230 ppm
ph after aging 8.4
i dont think at 230 ppm my kh will be low, never tested kh and gh.
Can crushed coral could control the 0.3 ph variation? donno how would crushed corals raise tds in relation.

What is the PH of your tank and the PH of straight tap?

Eddie

[champak]

ph out of tap 8.1
ph after aging for 24 hours is 8.4.
and tank ph before changing water is 8.1

[Eddie]

ph out of tap 8.1
ph after aging for 24 hours is 8.4.
and tank ph before changing water is 8.1

Why dont you skip the aging and just go straight tap?

Eddie

[mmorris]

You might want to check the Kh. It seems a bit odd that the ph should drop like that in 24 hours though. What is the ph from the tap after two days? Make sure when you age the water you aerate it. I don't have any measurable kh in my water so I add a little crushed coral in a nylon stocking to my canister filters. You really don't need to worry about tds until your fish start breeding and you want some fry. Is a 90% wc necessary? I assume you are growing out some juvies?

[Don Trinko]

TDS: People who breed fish use TDS under 100. MY tap TDS is 750. I mix 50/50 with ro. Tank TDS is typicaly 450 to 550. Don T.
PH: While my ph in the tank is abougt 7.6 to 7.8 my storage tank is 8.0 to 8.5. Fish tolerate a change to a higher ph than they do to a lower ph. Stable ph is best but plants and other things effect ph. As said before if your ph changes a lot check your KH. If KH is under 3 it can cause ph swings. Don T.

[Jhhnn]

TDS 750... Wow. Liquid rock. Right now, my tap water is ~150. I actually add a little salt to bring it up to ~200 or so. The fish just seem more comfortable there, a little less likely to be skittish, bolt like a flock of quail taking flight...

This thread, and others like it, show just how important it really is for hobbyists to test and understand their water. Armed with empirical data, it's a lot easier to understand what's happening and why. I didn't have a TDS meter until just recently, although I have all the other test kits. I rarely use the hardness kits or the pH kit at this point, because I already know what they'll say. The TDS meter is interesting, in that it confirmed what I suspected, what the Denver water board already told me, that my tap water has low salinity, a parameter that really can't be measured any other way...

There were times when I came back to discus keeping last April that I attempted to adjust the pH. At 50% water changes, new water .5 lower didn't phase my fish at all. At 90%, I couldn't really say what would do well. After learning a little more, I gave upon that, because my water is pretty stubborn- it'd bounce right back or nearly so over a day's time, anyway, and the fish seem entirely happy at my usual 7.4-7.8 range, which varies seasonally...

[jaykne]

My ph comes out of the tap at 7.2 and then due to gas injected chlorine goes up to about 7.8, I do 90% water changes straight out of the tap with no real stress on the fish just add prime for the chlorine. Larry

[pcsb23]

Generally speaking ph going up is better tolerated than ph going down. What really stresses the fish is rapid changes, not the amount it changes by.

As an example if you were to take a discus from water with a ph of 6 and then place it in water of a ph of 8 it would be quite stressed, if however the water with a ph of 6 went up to 8 over a couple of hours then the stress would be significantly less. The same applies to TDS, changes in TDS (Conductivity) afect the nervous system of the fish as basically they use this conductivity to sense via the lateral line. Big changes have big effects, again the rate of change is key.

One way to induce discus to spawn is to drop and raise ph by a whole point day in day out.

Aiming for stability is never a bad option and is usually better than trying for so called perfect water. The best advice I can give is to know your own water, and work with that.

[scuba guy]

is bio load responsible for ph swing? or its because of carbondioxide liberated by fish?

Lack of a buffer is what causes Ph swings. CO2 definitely will drop Ph dramatically without a buffer present...but the amount coming from fish is negligible compared to CO2 injection for plants. Calcium from hard water is an outstanding buffer. Unfortunately, Calcium limits Discus from breeding.

[pcsb23]

Bio load does have an impact on ph, not just from CO2 from the fish as has rightly been pointed out the amout they p[roduce is relatively small. It is from the end result of the nitrogen cycle, nitric acid, which is a strong acid, this can be significant depending on buffering etc.

[champak]

Thanks all of you
I noted that bio load plays the swing trick, hope i would find ways to control my bio load, any suggestions for reducing bio load in tank without reducing food amount? as i am raising juveniels.

[Eddie]

Thanks all of you
I noted that bio load plays the swing trick, hope i would find ways to control my bio load, any suggestions for reducing bio load in tank without reducing food amount? as i am raising juveniels.

water changes ;)

[pcsb23]

Thanks all of you
I noted that bio load plays the swing trick, hope i would find ways to control my bio load, any suggestions for reducing bio load in tank without reducing food amount? as i am raising juveniels.yep Eddie is right - water changes:bandana:

[exv152]

i dont think at 230 ppm my kh will be low, never tested kh and gh.

Can crushed coral could control the 0.3 ph variation? donno how would crushed corals raise tds in relation.

Noticed you mentioned that you don't test KH. IMO it's more important to test KH than pH for the simple reason that the first controls the latter. If you have a KH of 3 or higher in your tank, and in the WC water, you won't get any wild pH swings, regardless of your bioload.