A 100% W/C is like starting up a new tank and putting a whole bunch of corals in. Hey that's basically what I did well not that fast I waited every other day.

I usaly only did 20% but I moved my tank and/or redid stuff and 5 times I did 100% waterchanges. never lost anything on a 100% change or suffered any ill effects. just match salinity, PH and temp as close as you can, and away you go.

Steve

It's hard to get a debate going when everyone agrees with you :razz:


It's not very cost effective to do large water changes all the time, only when you have problems :lol: . In fact I'm reaching the point where I don't do water changes unless I notice problems starting :redface:

I think it would depend on what the problem with the old water is. The key is stability. If it just a routine water change where the new water was basically the same as the old water than a 90% WC shouldnt be harmful. If it is an emergency WC than a 50% change could be fatal. Eg. what happens if your tank has a problem and get a pH spike of 9.0 and so you do an emergency WC and thus cause it to drop to 8.2 in a matter of minutes? Wont be a pretty site afterwards. The cure may be more harmful than the disease?
I think you need to know exactly what the condition of the old water is before we make large WC. Would kind of be like adding new corals and fish to our tanks with no acclimation what soever

Well I've been thinking about that theory, that corals get used to bad water conditions and giving them clean water conditions will make them react negatively but I just don't think thats true.

If you live in a smoky house and end up with emphysema and then move out into the fresh air, it's not the fresh air that kills you, Your just too late in moving out of the house. And i think it's the same with corals, sometimes they are just too far gone for a complete water change to save.

Oh and I have raised my tank ph from 8.0 to 9 in a very short time (adding kalk too quickly in a tank with no sump :redface: ), it wasn't a problem

Corals are actually hardy creatures that can take all kinds of abuse temporarily (inluding sitting in a stainless steel sink for 3 hours and then having a cold coffee bath, can anyone say acidic :lol: ) but the key word is temporary.
It's making them live under foul conditions for a long time that does them in. They are wild animals and like all wild animals they can't afford to "look sick" or they will be eaten so they "look" healthy until they are just about dead

I once pruned my tank and put some less desirable acros in my back deck in July (shaded area). I changed my mind on one of them about 2.5 hours later and put it back in the tank. I had it for years afterwards. Yes, a healthy coral can put up with a lot. And since they really like water, giving them clean fresh stuff shouldn't cause a problem.

I've noticed that when I've ordered frags and they come overnight in a little baggies, I've had more success (less mortality from shipping stress) when I've just taken them out and put them in the tank. Temperature, pH, ammonia, nitrite, nitrate, whatever whatever, surely all hugely different, and yet they live better than when I do a slow drip over a matter of hours and have everything slowly temperature matched.

Now, having said that, there are things I'd still do a drip on. Clams, urchins, shrimp ... But corals ... yeah surprising but the slow drip doesn't really help them. Take them out of the cruddy water and put them in good water faster and they recover faster. I think the "smoke in the house" analogy is spot on. If the fresh air kills you then you were done for already.

Congrats. on 8000 posts!

Oh my :eek: do I ever need to get a life!!:redface: