- Messages
- 691
- Location
- Sisters, Oregon
Best of luck Dave, it would be my suggestion and hopefully it will get them back to being successful. It was reading some of yours (and Mikes) posts on "the Krib" that first got me interested in Apistogramma, when I came back to fish keeping after many years away.I am going back to the old schedule--RO, Catappa leaves and Peat.... No more Ph tests, they dont read true.
Interesting, was it actually harder? I ask because we have a had a lot of people finding similar things in the N. of the UK, where the pH in their tap water has suddenly become much higher, and we think the reason for this is the addition of sodium hydroxide (NaOH) by the water companies, added because of the new tougher rules on heavy metals in drinking water. This raises pH, but doesn't offer any buffering and a lot of people were adding acids to reduce the pH, and finding that the pH suddenly flipped from alkaline to very acid, once the OH- ions were exhausted.it was harder with a Ph of 7.9
I know exactly what you mean, it has taken me a long time to, hopefully, fully get my head around pH and buffering, but I think I now understand it and I can visualise what is actually happening in the tank.The idea of "ignoring pH" in very soft water still makes me squirm just a bit
Now that is really interesting, and not what I would have expected, but this is when you can't beat experience. Interestingly I was talking to a well known Bristol "L number" breeder recently and he uses an RO/HMA water mix (with Terminalia catappa leaves) at about pH6.5, but at much higher conductivities (180 - 200ppm TDS) than I would have expected.The least important factor, IME, is TDS/conductivity. When the dissolved solid is something relatively inert and does not affect pH or KH, there is wide range of tolerance that the fish will accept. The way I lower the pH in the Parananochromis breeding tanks is to use a pH reducing chemical (Kent Marine's pH Control Minus), which uses NaCl as the binder for the acidifying ion. When I use it in low hardness (KH) water to reduce the pH, my TDS rises from >20 ppm (>40 mS) to over 150 ppm (300 mS). The fish still spawn and behave normally. I have seen this happen with other species too: Apisto. panduro, Congo. sabinae, Dicrossus filamentosus, Nano. transvestitus and numerous tetras, barbs, rasboras and Betta sp.
I think that the most important factor for the physical act of egg fertilization and development is KH. If it is too high there is a poor fert rate. That is why I use R/O to breed any soft water fish. Even when the fish do not seem to care behaviorally, I get better results in low KH water..[/I]
Unfortunately we are now into territory where I haven't got any knowledge, I was always interested in plants and ecology and as far as possible I avoided any animal physiology, even at school.BUT - Does that mean an obligate soft-blackwater fish is perfectly happy long-term at pH 9 (and can reproduce without a badly skewed sex ratio) if the conductivity, GH and KH are really really low?
I think this is what Ted is saying, that you can stabilize pH with NaCl, and that this doesn't effect any other parameter, and the fish themselves are as happy at 300microS as they were at 30microS. My initial hunch would have been that conductivity does make a difference, but this looks not to be the case.And what about pH influence on a fish's O2 uptake, mineral uptake, CO2 & ammonium excretion, etc, etc -- or is pH not relevant to those processes when total ion content (conductivity) is really really low? IF pH still has some fish-physiology significance in ultra-soft low-cond water (I can't quite let go of that yet Darrel) then would adding a small amount of NaCl into R.O. or rainwater (maybe 1 teasp per 10 gal = about 300 uS) help to STABILIZE pH (without actually changing pH), since Na is a top-notch proton acceptor and Cl is a top-notch proton donor?
I think this is what Ted is saying, that you can stabilize pH with NaCl, and that this doesn't effect any other parameter, and the fish themselves are as happy at 300microS as they were at 30microS. My initial hunch would have been that conductivity does make a difference, but this looks not to be the case.
(another Tom Barr finding, you can have high CO2, as long as you have enough O2, without asphyxiating the fish).
Ted - what about GH? I thought it was the Ca and Mg ions (GH) that interfered with fertilization in soft water fish, not the carbonate & bicarbonate (KH) ions?