Water changes

[marie]

I'm mostly just curious but everytime someone has problems with their tank and water changes are recommended they are told never change more then a 10%-20%.
Every water change on my smaller tanks (50g), I change out 50% and never had any problems what so ever. I'm not even that precise in matching salinity although it is usually close.

How many people have actually had bad things happen if they do a large, say 50% or more water change? I don't mean when the bad batches of salt were around or when you are changing salt brands. I mean regular everyday water changes, when you've used salt from the bucket before and know what the cal/alk is.

A large water change makes so much more sense when you are having issues and yet everyone recommends lots of smaller changes which takes twice as much new salt water to reach the same goal

I think I should of made this into a poll :lol:

[Pier Pressure]

We change about 30% out of our 28 gallon once per week and we have a fairly large bioload. We did lose a batch of fish overnight once but the corals and inverts were okay so we still aren't sure what that was about. Some kind of weird spike. No other problems and everything seems healthy. We have had this tank up and running since November of 2006.

[justinl]

i always recommend (and do) weekly to biweekly 20% changes. it's just so that you're not drastically changing your params in a very short span of time. for example, i dont bother heating my water before a change, so a large change could bring down my temp really fast. salinity might change too if your not careful with top off. etc etc.

i think there is a more safety in smaller more frequent changes, rather than the larger infrequent changes (which would cause more stress during the change process). while it is on the large-ish side, i dont think 50% is really big... 75% would qualify though. 100% is a definite no no in my books.

during emergencies, large cahnges dont always make the most sense. I agree that sometimes it's a good idea, but certainly not always. especially if you're not really even sure what the problem is. a 30% change during those times, i think is enough most of the time just to give you time to figure out what your problem is.

[marie]

during emergencies, large cahnges dont always make the most sense. I agree that sometimes it's a good idea, but certainly not always. especially if you're not really even sure what the problem is. a 30% change during those times, i think is enough most of the time just to give you time to figure out what your problem is.

I think I disagree with that, unless you pick up a bad bucket of salt (which can happen) I can't think of any problems that can't be solved with a large water change. (I'm not talking about hitchhiker crabs, aiptasia, fireworms or the like kind of problems)

Edit, Ok I lied I just thought of one instance and that is starving corals

[Quagmire]

I do 50% weekly water changes and have never had a problem.I try to match salinity,temp and buffer my alk couple dkh higher, ph is usually close .But they are never an exact match.The only problem I can think of when doing a large emergency w/c,as long as parameters are in order might be light shock due to better light penetration in clean water.Think of the ocean,an area the size of our tanks get a 100% w\c numerous times a day.

[justinl]

well unless you have already identified the problem, i think the problem with the large changes, given that the new water is good and temperature matched as well, is that something will be changed drastically... and not necessarily something you can/do test for. there's so many things that might be off taht we just cant account for... we dont even know the complete chemical composition of real seawater. while a large change can be good, it's not something to be done blindly or regularly imo. if you do know what the problem is, then yes, act accordingly.

yes i agree that a large change can solve quite a few problems, but most times, the aquarist doesnt know what the problem is (which is my point), and there are inherrent risks in a large change itself. i suppose it's a balance thing. does the risk outweight the benefit, or vice versa? i dont think we can generalize that.

Q, yes, a single area of a few gallons in the ocean does get a 100% change many times a day, but that is not a rational comparison due to scale. it's like taking a look at one cubic centimeter of our tank and saying, that it gets 100% water change numerous times a day within our tank. but a change with what? the same water that was previously occupying it. so really, nothing changes. i suppose you could say the ocean is a small tank with a near infinitely large sump... which obviously cant compare to a closed system tank.

[marie]

yes i agree that a large change can solve quite a few problems, but most times, the aquarist doesnt know what the problem is (which is my point), and there are inherrent risks in a large change itself. i suppose it's a balance thing. does the risk outweight the benefit, or vice versa? i dont think we can generalize that.

But what are the inherent risks exactly and are corals stressed by a large water change (other then being out of the water for awhile which happens in the ocean at low tide all the time anyway).
If you are using the same salt that you always use and the salinity and temp are matched you should be good to go.

This is what I'm curious about, has anyone done a large water change, stressed their corals to the point of dying and can definitely say it was the water change that did it?

[Rippin]

One other thing to add to the mix - if you change in the range of +40%, then many of your corals that are near the top are out of water. For a short time, this does not pose a problem, but if you're slow to refill would this cause added stress? Especially if the water change was initiated by a problem? I would think that with such large water changes the MH lights are turned off so that it doesn't cook the corals at the top.

[marie]

One other thing to add to the mix - if you change in the range of +40%, then many of your corals that are near the top are out of water. For a short time, this does not pose a problem, but if you're slow to refill would this cause added stress? Especially if the water change was initiated by a problem? I would think that with such large water changes the MH lights are turned off so that it doesn't cook the corals at the top.
There are corals in the ocean that spend a few hours out of the water at low tide they get cooked by the sun and rained on, but yes If I'm going to be more then half an hour then i will turn the MH lights off

[Quagmire]

Q, yes, a single area of a few gallons in the ocean does get a 100% change many times a day, but that is not a rational comparison due to scale. it's like taking a look at one cubic centimeter of our tank and saying, that it gets 100% water change numerous times a day within our tank. but a change with what? the same water that was previously occupying it. so really, nothing changes. i suppose you could say the ocean is a small tank with a near infinitely large sump... which obviously cant compare to a closed system tank.


I don't think the comparison is off at all,assuming you have parameters in check.Say in the ocean a clam dies,the current replaces the foul water around the clam which dilutes and dissipates.Althogh the replacement water come from the same body of water,it is fresh and clean,where as the old water was foul.If you are using the same salt,mixed to the salinity,at the same temp and PH,for a water change,then it is no different than what is in your tank,only fresh.
I'm not saying the w\c will fix the problem,if the above dead clam was in a tank you would have to get it out or the tank would foul again.
But the w\c in itself won't cause a problem,aside from the possible light shock mentioned in my first post.

[Quagmire]

One other thing to add to the mix - if you change in the range of +40%, then many of your corals that are near the top are out of water. For a short time, this does not pose a problem, but if you're slow to refill would this cause added stress? Especially if the water change was initiated by a problem? I would think that with such large water changes the MH lights are turned off so that it doesn't cook the corals at the top.

My corals are out of the water for about 10 minutes or so when I change water,no problem.But as Marie said,if its going to be a while,its better to turn them off,just to be safe.

[ron101]

I think I disagree with that, unless you pick up a bad bucket of salt (which can happen) I can't think of any problems that can't be solved with a large water change. (I'm not talking about hitchhiker crabs, aiptasia, fireworms or the like kind of problems)

Edit, Ok I lied I just thought of one instance and that is starving corals

I agree. If the water has some sort of contamination a small water change is unlikely to lower the concentrations enough to fix the problem. Of course you dont want big temperature or salinity swings but those are easy enough to match up.

Many reefs are close to the surface and experience salinity changes with rain. It doesn't wipe them out.

[Aquattro]

Personally, I think as long as the water is the same temp and salinity, change as much as you want as long as it's the same bucket of salt. If it's a new bucket, I'd test a few more things, pH and Alk specifically. I would of course suggest that there is some degree of confidence that the water is the issue. I've done up to 90% changes before with no problems other than using most of a bucket of salt. Make sure it's pre-mixed for a day though, or heavily mixed and aerated if required same day.

[EmilyB]

I agree the pre-mix for 24 hours or so, when doing such a large water change. I couldn't do 50% in a 230g, impossible, but I would have loved to.

My FOWLR has a few softies/LPS and been set up several months now skimmerless. I think the 50% waterchanges make all the difference there.:wink:

[SeaHorse_Fanatic]

I have done 50% water changes many times before & when I upgrade my tanks, I usually use 40-50% of the original water & add new water for the rest. I find my corals loved these massive water changes (as long as salinity & temp. were close). Two weeks ago, I did roughly 120g worth of water changes on my main system & everything is thriving.

Anthony

[tang daddy]

I never have to drain the main display for waterchanges only the sump, therefore the corals remain in water but I find large water changes good for certain corals ie softies but not too well for sps anyone agree?

[marie]

I never have to drain the main display for waterchanges only the sump, therefore the corals remain in water but I find large water changes good for certain corals ie softies but not too well for sps anyone agree?

I've never had a problem in the past with large water changes and sps. Of course the last 18 months all my sps are in my 175g and I don't have a mixing bucket big enough to do a large water change, I wish I did :lol:

[Delphinus]

I did a 100% water change once, solved my nitrate buildup pretty lickedy-split :lol: But it was a 20g tank and it had no fish, only a carpet anemone and some corals. But they all liked the outcome ... :)

There are times when I look at my 110g cube tank now with its elevated nitrates and I wish I could do a 100% changeout, I just don't have enough reservoirs to do it (and I have fish in there so that's no good). But I'd love to be able to change out even 50% or 75% of it just to be a kick-in-the-melon to the nitrates that are there.

Other than the bad salt (Kent, about a year ago? Maybe 2 years ago now, when they had that alk issue??), I've never had an issue from the waterchange itself. But yeah, I do match the temp and SG carefully, and do the premix for 24 hours thing too, so that probably helps a bit. I'd hate to see the results of a large scale water change that introduced a drastic temperature change.

I tell you one thing though, and maybe it's worse for me than others since I have tanks that have at least 5 years of crud buildup in the plumbing, when I turn the pumps off and turn them back on, the stuff that comes flying out of the sump return outputs is something I wonder if it would be better off not having been disturbed and released "en masse" into the water (ie, did I just invalidate my water change). I need a way to scrape out the pipes :lol: Or maybe it's better just to redo the plumbing every few years or so :eek:

[marie]

It's interesting that nobody is speaking up for the small water changes.

It was comments like this


Well I had done a 50 % water change a few days ago(risky I thought myself )
and this

Really what I would do is (here come the flames) a 80 or 90% water change

that got me curious.

It's not just canreef but on every reef forum I visit, there is a group of people who will tell you to never change out more then 10-20% of the water. I think that a lot of tank crashes could of been saved over the years if people were more willing to trust the lone person who says "Do a 90% water change" :biggrin:

[Aquattro]

Marie, I completely agree. While I regularly do 10 or 15% changes for maintenance, if I thought I had an issue that a 100% change would fix, I'd do it ( well, back when I had a 100g tub for mixing). The "rule" of 10% is just being safe and we always tout "make small changes slowly" in a reef, but properly prepared water is just like the water in the tank without all the crud in it.

[tang daddy]

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.

[StirCrazy]

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

[marie]

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


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 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:

[PoonTang]

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

[marie]

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

[marie]

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

[Aquattro]

Corals are actually hardy creatures that can take all kinds of abuse temporarily

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.

[Delphinus]

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.

[Sebae again]

Congrats. on 8000 posts!

[Delphinus]

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

[Sebae again]

Just think of it as a lifestyle.

[PoonTang]

Some creatures will tolerate larger changes of certain parameters than others.
You had better know which and how much if your going to do a large change or run the risk of killing things.
Marie...do you drip? and why?
Essentially acclimating is a series of small water changes so as not to shock the creatures.

[marie]

Some creatures will tolerate larger changes of certain parameters than others.
You had better know which and how much if your going to do a large change or run the risk of killing things.
Marie...do you drip? and why?
Essentially acclimating is a series of small water changes so as not to shock the creatures.


Only when I have a cold and everyone can get there minds out of the gutter :razz:

Not saying everyone should do as I do (in fact you probably shouldn't) but the only animals I ever acclimate are shrimp and thats because I didn't once and the poor things were dead within a week. Everything else fish, urchin, crabs and corals all get dumped in as soon as the temps reach equilibrium and I have never lost anything.For snails, I tried R. Shimeks method of taking them out of the bag letting them dry for 20 min and then placing them in such a way that they find there own way down to the water...it worked wonderfully :mrgreen:

[marie]

And for every one who ships corals I've been trying an experiment dry shipping monti digitatas. I wrapped the montis in a J-cloth soaked in tank water, placed in a bag and filled with air. I sent it to Anthony by overnight and they made it to his place alive.

Next i'm going to try a piece of my stag but I think I'll wait until the weather warms up

[PoonTang]

Starfish are very slow acclimaters too ive heard. Infact i was told to be very careful as to where my Linkia was when i dumped in fresh makeup water. BTW i have heard that zoas are sometimes shipped in wet newspaper.

[christyf5]

Last year during Charles Delbeek's talk at Big Als he mentioned that they regularly ship corals with 6 pack rings (or some sort of plastic type wrap that looked like 6 pack rings). They dip the rings in water a couple of times to get them wet, then wrap them around the corals and pack them up. He said it worked like a charm and saved huge money on shipping a ton of water :biggrin: