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RE: Ammonia Quandry

FMarini — Thu, 08 May 2008 14:36:37 GMT

Thanks Guys-- (Kathy too)-- I've been out of town.
Okay IMO the main reason to do a water change when you have increasing ammonia is to dilute the problem (remember the solution to pollution is dilution). while you guys bring up an excellent point about pH issues, I've found over the years that its kinda moot, in that most folks don't have too extremes in water pH. After Ro/Di treatment the water can tend to be slightly acidic, but not too much and conversely i seldom if ever have seen high pH water. So while matching pH is excellent in theory, in practicallity taking clean temp adjusted FW water is usually sufficient.

Now if your pouring water straight from your tap into the tank--- then we can talk about this

RE: Ammonia Quandry

jjsmommi2 — Wed, 07 May 2008 07:15:35 GMT

oh that is very interesting and makes perfect sense. thank you for the food for thought. i love networking with other hobbyists

RE: Ammonia Quandry

KathyL — Tue, 06 May 2008 20:22:39 GMT

Yes, raising the pH makes ammonia more toxic, because it drives the equilibrium of ammonia and ammonium cation towards ammonia, which is more toxic than ammonium. Yes, doing a water change with ammonia free water, that is the same pH as the "dirty" water, will lower the ammonia concentration without harming anything.

From an EPA pdf I googled:
pH has a strong influence on the concentration of un-ionized
ammonia in water, such that a variation of ± 0.1 pH unit during the test my
result in ± 25% variation in the NH3 exposure concentration.

Make sure pH matches, and you are good to go.

There is a method of acclimation of freshly shipped fish that attributes greater survival not to dripping tank water into travel water, but to adjusting temperature and pH of tank water to shipping water after the fish arrive, and then plunking the fish into the oxygen rich, ammonia free water as soon as possible.

Shipping water is typically acidic due to the exhaled CO2 from fish breathing, and high in ammonia, due to fish wastes. As long as the pH is low, the fish are fine, if a little oxygen starved. Opening the bag and dripping tank water raises the pH dramatically, making the bag's water's ammonia more toxic, and the ammonia INSIDE the fish more toxic. The plunking method allows the fish to slowly come to ammonia equilibrium with ammonia free water, and provides it with greater oxygen sooner. One can then slowly increase pH and temperature in the tank, without stressing the fish, and without the threat of ammonia toxicity. I think this is really interesting...

Ammonia Quandry

jjsmommi2 — Tue, 06 May 2008 11:17:51 GMT

This is a bit off topic but,

In regards to ammonia toxicity, I was under the impression that doing a water change on a tank with high ammonia is the very worst thing you can do, i was told it would 'give the ammonia new ions' and make the problem worse. Now reading into it, I see nothing but recommendations to change the water. I'm guessing I was told that because in theory the ph would rise if you did a water change and therefore the actual ammonia, not ammonium, would spike. But what if your ph is the same as your change water, then there would be no problems, right? Or if you added Amquel or something of that nature to the change water then it wouldn't matter at all. This is important for me to understand, as I have a snail system that is having issues.

Thank You