Water Changes?

[Goon]

Hi All,

What are everyones thoughts on waterchanges... do them at all? how often ? how much ? and of course why?

I have done some searches through the forums and have found everything from people not doing water changes at all ( fairly rare ) to people doing water changes every week (seems like major overkill )

Now I may be wrong, but from what I have read ( in various books, which I will admit may be alittle outdated ) the water changes serve 4 primary purposes.

1. Dilute nitrates -- From what I have read in various posts, and sites, with a proper DSB and enough LR this should not be an issue at all - the nitrate gets turned into nitrogen gas which exits the tank.

2. Dilute various trace elements in the water -- This was an issue in the past if not using rodi because with water evap excess traceelements were left behind then when you add more tap water there is even more trace elements. If you are using a proper RODI unit this also should not be an issue.

3. Clean the gravel -- Again with a proper DSB this is a non issue ( in fact you want to avoid doing this as it can destroy your DSB)

4. Disaster Control -- Dilution of various agents in the water when there is already a major problem. This is not a day to day need only if there is a disaster.

Am I missing something. If these are the only reasons then are water changes necessary at all? With a descent volume tank (bigger being better) that has an established DSB and adequate LR, and of course is not overstocked won't the tank reach an equillibrium (yes I know I can't spell) that won't require water changes, just topoffs to replace evaporated water.

Obviously per#4 in a situation where there is something seriously wrong in the tank water changes are very prudent to potientally get rid of or dilute what ever is causing problems


Sorry for the long post,
Thanks in Advance,
Bryan

[Nek]

You touched on some key points. Take number 4 for example. Why would you wait for a potential disaster to dilute contaminants?? If you were following a regular change schedule, this disaster probably would not have happened.

Also, some nasties are introduced into our tanks by sources beyond our control, ie. food, hands in tank, etc. Over time, these will build up.

Secondly, you said nothing about REPLACING trace elements utilized by the fish and corals. This I believe is the number one reason for changing water.

That being said, I change 5 gallons a month in my 5 year old 72. Not alot, yet it is something.

[Goon]

Nek,

Thanks for the response. Good point reguarding various contaminates that will get into the tank over time from hands and what not.

Another question that I now have is what is in rodi water. It was my understanding that rodi water had no (or next to no) traceelements. Isn't the purpose of rodi to make the water as pure as possible. From books and some posts that I have read depending on what you keep you need to ocassionaly add suplements if you use rodi water because there are no trace elements in it good or bad.

I am just trying to piece togather all the information that I have gotten from different places to get a better understanding of how everything works before I try to start a saltwater tank myself :)

Also anyone else out there please chime in :)

Bryan

[tendar]

Hey Goon
Another arizona reef cool.

I do water changes once a month of about 15-20% for several reasons.
Replenish used up trace elements and dilute trace elements that build up.
Helps keep up calcium and removes nutients
I look it like changing oil on your car. You dont run the same oil for the cars life because it breaks and gets dirty so needs some new oil now and then fresh clean with every thing a body needs.

True some people dont do water changes or very little but ask them what happens when they finally do a good 30% water change which is usally what they do when they dont do any for a long time and bet at least half will admit that the corals start growing faster and looking better after week.

RO/DI water is pure clean water. The filters pull out all the cataminets the the city puts in it so it is safe you and the average Joe to drink and not die. :eek2: (over acting there) Ecspecially here in arizona. I test the water out of the tap here in tempe and it is 575 ppm on a TDS tester, that is pretty high.
Your salt adds pretty much all the trace elements you need but corals use them up some trace elements faster than others depending on what you keep for corals so adding some trace elements is used to help allong with water changes.
The trace elements in tap water is not the trace elements you want like chlorine, floride and copper and who knows what else.

[Goon]

Tendar,

Thanks for the reply, yes it is good to see other Arizonians on the board :) Very good point on the traceelements added to the salt mixture. I had read about that but had completely forgot.

Everyone,

From what I have recieved so far the concencious seems to be once a month and anywhere from 6.8% (5 gal from 74 ;) ) to (15 to 20%) anyone else want to add anything?

[RIVERROBSKI]

See here is were everyone has a different opinion.This is why I stick with one experience reefer.I do 10% a week in omy 55 gal.Been set up for 9 mnths.2" sand bed/canister filter.Have had no problems.Take a look.When I first started out it was confusing.so many reefers,so many opinions.for 8 mnths istaright water test have been perfect.

www.robreneasreef.com

[IndyMathWizard]

few thoughts...

first, you CAN spell....good for you ;)

secondly, keep an eye on your nitrogens.....NH3, NO2, NO3....when you first start, you MUST change water to eliminate these....IF you have livestock. It is actually a good idea not to change water while you are cycling, if you can help it. Once your DSB is established, as long as you are using RODI, IMHO you needn't change water. Top-off water provides "freshness" and the natural filtration makes everything else good. Of course, additions like calcium supplements, the list goes on, will be necessary. You cannot add these with RODI water anyway.
All that being said, it still just makes common-sense to change some water every once in a while. Even when you use wet-dry technology, which promotes nitrate, the owner of Inland Aquatics ( i only live an hour away from there) told me 15% once a month is enough. My two cents, whish is still really only worth about 2/3 of a cent.
Matt

[Nek]

"It is actually a good idea not to change water while you are cycling, if you can help it."

Indy, can you explain??

[Just Fishing]

I agree that water changes should be done on a reef. I change 10 gals every two weeks from my 55. As stated earlier you add trace elements to the tank and use remove things from the water that you do and don’t test for. Replacing top off water adds nothing in the way of trace elements. I also agree that you shouldn’t do water changes when cycling a new tank. By doing a water change then I believe cuts down the bacteria growth during the cycle. After the tank has cycled then do a water change.

[Nek]

Its been about 5 years since I 'cycled', so excuse my ignorance. Isnt the purpose of water changes during the cycle to remove toxic levels of ammonia to give the bact. a chance at survival??

[DgenR8]

I change 20% of my water every week, I'm still doing it, but am starting to reconsider. Dr. Ron has recently ststed that the synthetic salts we use add trace elements in much larger proportion than what is found in NSW (Natural Sea Water) Many of these "trace elements" are havy metals that can be very harmfull at high levels. Copper, for instance.
I still see a need to remove "used" or "worn out" water from my system, Dr. Ron has succeeded in making me think twice about my source of salt water for changes, not the need for changes.
20% weekly might be on the high side, but my system shows undetectable levels of Ammo, Nitrite, and nitrate. Could be my DSB, or live rock, could also be my low fish load. In any case, I like the fact that these toxins are not present in my tank, and until something better comes along, I will continue to change 20% weekly, with my IO synthetic salt mix, as I don't want to make changes to something that appears to be working for me.

[Goon]

Thanks for the replies everyone. I figured that I would get a wide range of answers ;)

Here is one more question. Would a larger tank (180 gal) with a really low stocking level change anyones ideas on frequency or volume of water changes?

I may pick up a used 180 at a really good price, but I would not be able to stock it with too aweful much for quite some time. About the only thing holding me back at the moment is the thought of changing 36 gallons a week (20% a week). Even 27 - 36 gallons a month (15-20% a month ) combined with water top offs would add greatly to my water bill ( not to mention the cost of IO over time ) and all the work to pull that off.

And for cost reasons I probally would start it as FOLR then change to reef over time as $ will allow (obviously planing my filtration and lighting with a reef tank in mind). But even as a FOLR I wouldn't be able to put but a couple fish in it for quite some time.

Obviously at some rate it comes down to what I am comfortable with, just trying to get an idea what that is before I sink a bunch of money into a 180 gal tank.

On another note, assuming again a light bioload, can I get away initially with just a DSB and LR for filtration and have powerheads to move water around. I would drill, put in bulkheads, and plug them before putting water in it so that eventually I could add overflows and a sump below ( and possibly even a refugium). The tank measures 6 foot x 2 foot x 2 foot. Again I am talking for the moment about a 180 FOLR with only a handfull of fish (hope to go reef in the future at whcih time I will make necessary changes)

Sorry for the long post again (gotta learn somehow ;) )
Thanks in advance for any advice,
Bryan

[IndyMathWizard]

Sorry for the late reply. The reason you want to try and leave water in during the cycle is so that the bacteria don't starve. Otherwise you could, I guess, "feed" the system every day, like put in some fish food or some grocery store shrimp or something. You want the ammonia to go up, because you want the bacteria that take care of it to have something to live on. Changing out "poisoned" water also takes away those crucial bacterium's food source. only my experience and opinion, and rememebr, my two ceents is still only worth about 2/3 of a cent ;)
Matt

[RIVERROBSKI]

I do believe water changes are needed during cycling.

[DgenR8]

Here's how I see it,
If you do water changes while you cycle, you will remove the nutrients that feed the bacteria you WANT. How much "harm" that does is debatable. Some will say that you'll have a "weaker" cycle if you do water changes. I don't think so, you are cycling to grow bacteria, you don't need a ton of bacteria after the cycle if you stock the tank responsibly. Moderate stocking, done slowly will provide time and nutrients for the bacteria you want to establish itself at a level comperable to the amount of waste your system produces. I see no problem with doing periodic water changes while you cycle.
NOT doing water changes during the cycling process, IMO will cause more of the life on your live rock (making the assumption that you are cycling with rock, not fish) to die off. You will lose more of the prized hitchhikers, and have much higher levels of ammonia, needing much more bacteria to consume it. After the cycle, there won't be nearly as much Ammonia in the water, and a ton of bacteria will die off, as it has no food. I can see NOT changing water extending a cycle, not shortening it.
I advocate water changes while cycling, for those reasons.

[IndyMathWizard]

Good points....I will consider these. thx

[Just Fishing]

Larry made some point that I haven’t thought about. Especially this one.

NOT doing water changes during the cycling process, IMO will cause more of the life on your live rock (making the assumption that you are cycling with rock, not fish) to die off. You will lose more of the prized hitchhikers, and have much higher levels of ammonia, needing much more bacteria to consume it

I’ve changed my view on water changes during a cycle. I see that there is some times that a water change is need during a cycle. Especially when your have a lot of live rock or are using live stock to cycle that would otherwise die if you didn’t. I don’t recommend livestock btw. Thanks for the explanation Larry.

[Nek]

What, and you give me no credit???:rolleyes: :D :D :D :D

[Just Fishing]

Sorry Nek you help with the change in opinion too but Larry pushed me over the edge.
:lolspin: :lolspin: :lolspin: :thumbsup:

[IndyMathWizard]

I can agree with the die off of live rock due to ammonia poisoning. My only concern with this new opinion I am formulating is: if I am changing water to dillute ammonia, how can I monitor the cycle accurately? I have always tested DAILY during the first month of a new tank. Thoughts, Larry or Nek?

[Nek]

Im not advocating changing out the whole lot, just say 10 percent. It will be near impossible to get ammonia to 0 with water changes alone, unless you change 100 percent.

Once you no longer detect amm. than your cycle is over.

During the initial cycle, amm. will rise even after a water change. Then you will see it stabilize, then you will see it lower.

[DgenR8]

I agree with NEK, just one thing I think he got wrong there.
Ammonia is the beginning of your cycle, it will spike and drop off while Nitrite is spiking. Once nitrite has spiked and dropped to undetectable levels, you can consider your cycle complete. From there, you'll have to deal with nitrate, but that's much less toxic than Ammo or Trite, and you can begin to introduce livestock before you get it to undetectable levels.