No water changes

[zak.payne]

I've read a few threads that go back the last couple years, but I haven't seen much recently of people doing this. The infamous no water change method. Now, I understand the importance of water changes and whatnot, but I'm curious if anyone here has done this method and if you've been successful? From what I gathered, it's a matter of having the balance of removing excess nutrients and then dosing to keep the water levels sufficient for your corals. It seems easy enough, however I'm guessing I'm missing something...

[TimeConsumer]

Just because it can be done, doesn't always mean it should.

But yes I've seen folks run beautiful tanks without water changes. Sanababit's comes to mind in this thread: http://www.reefcentral.com/forums/showthread.php?t=1885414 He just did an ATS, no skimmer most of the time, and a calcium reactor.

[CStrickland]

GlennF has a beautiful no water change reef. Unlike some people that brag about how dirty their tank is, he does a great job of explaining the work that he does instead of the water changes:
http://www.reefcentral.com/forums/showthread.php?t=2395250
For me it's easier to just do a wc, but I really like the idea of conserving water. I mean, for my 120 I'm going to be wasting thousands of gallons a year just making rodi. We don't have shortages where I live, but for people that do it could be the diff between not having a tank.

I think it's a good direction for the hobby to move in for that reason, but I'm not sure it's any easier.

[zak.payne]

With my tank only being 24 gallons, a water change schedule will definitely be used. But I want to learn about the process if I were to ever upgrade to a larger system in the future and want to conserve water. There is a lot of science behind no water changes!

[BigCountry74]

i have not mixed salt in 3 months. if its not broke dont fix it :D

it all depends on the tank/setup I guess, and experience. and what your growing. filtration being the most important. every tank is different. this is what makes the hobby so cool.

most the newcomers I see on these forums run these tanks so under filtered. and overstocked to boot. and that = bad outcomes lol

[Ou8me2]

I've done it for years on my larger tanks, but no real success on smaller tanks. I definitely wouldn't recommend it to someone who is just starting out in this hobby or is fairly new.

[Timfish]

Our systems will last decades and decades if properly cared for. People have gone without water changes for a few years but without water changes waste products will build up in a system. Nitrates, inorganic phosphates and ammonia can be tested for but we cannot test for organic nutrients nor can we test for Dissolved Organic Carbon (DOC) which skimming does a poor job of removing and is best removed with water changes.

[CStrickland]

That's a really good point about long term viability. Like with my tank, after a summer away things started going downhill just from modifying the wc schedule to suit a sitter.
I should've mentioned that I believe Glenn's tank is pushing 10 years.

[dkeller_nc]

It can be done, but most that do and are successful at it do a great deal more than just "no water changes". GlennF's tank is a good example - he uses what he calls "Dutch Synthetic Reefing" where a great deal of trace element testing and supplementation is used to prevent depletion of essential elements as time goes by. Advanced Aquarist did an article on the method and the tank here (http://www.advancedaquarist.com/blog/glennfs-1500-liter-reef-using-hisdsr-method).

Another active member with a very nice tank that previously used a rare-to-no water change method is Mhucasey - his tank blog is here (http://www.reefcentral.com/forums/showthread.php?t=2468548).

Here are a few opinions on this - take it for what they are (opinions):

1) It's not for beginners, period.

2) One generally must employ a calcium reactor (or have a very lightly stocked tank where Ca and Alk can be supplied with kalkwasser alone). Otherwise, 2-part dosing will inevitably greatly skew the ionic balance in the tank water without any water changes, and some sort of trace element supplementation is probably going to be necessary, though food will make up for some of the depletion.

3) Nutrient export needs to be very carefully managed, but of course this is true in any tank - water changes aren't a good way to manage nutrients unless one is referring to a nano/pico tank that gets extreme water changes (sometimes up to 100% every week or two).

4) Most folks motivation for using no-water-changes as a strategy are looking for tank water stability, not cost savings.

Overall, I would suggest to someone considering this that saving water is a very, very poor reason for adopting this method. The amount of water one uses for an average-sized reef is vastly exceeded by day-to-day uses for bathing, cooking, laundry and other mundane household activities. So even saving 100% of the water use for a reef will make little to no difference (and isn't possible, since a great percentage of water use in reef-keeping is evaporation make-up). The salt one uses for water changes is also, overall, a very minor expense compared to the other outlays involved in reef keeping. And the risk to the health of one's animals is far greater than those cost savings justify, particularly if one is fairly new to reefkeeping.

If the thought is resource-saving (always a good thing), there's aspects of the hobby that are fairly easy to accomplish, and represents a near zero risk to the animal's health - power. Reefs are power-hungry by their nature, but a reefkeeper can do a lot to affect the amount required. Using efficient, DC propeller pumps for in-tank circulation and minimizing the size and power of the return pump is a big factor, as is minimizing evaporation loss from the tank as a means of saving on power for heaters - approximately speaking, evaporating one gallon of water from a reef per day is the equivalent of running a 100 watt heater, continuously.

If, however, one's motivation for the no-water-change method is intensively managing almost all aspects of the tank's water chemistry to provide the ultimate in "ocean matching", and one is willing to pay the rather large cost to do so, I believe it has a place in advanced reefkeeping that may provide a means to keep certain creatures in captivity that are now nearly impossible to maintain in good health in a tank.

[TimeConsumer]

Overall, I would suggest to someone considering this that saving water is a very, very poor reason for adopting this method. The amount of water one uses for an average-sized reef is vastly exceeded by day-to-day uses for bathing, cooking, laundry and other mundane household activities. So even saving 100% of the water use for a reef will make little to no difference (and isn't possible, since a great percentage of water use in reef-keeping is evaporation make-up).

Nailed it.

[Tweaked]

The couple friends I knew going the no WC way now change water weekly religiously after a huge crash. Was the crash due to not changing water, who knows, but their tanks quickly turned around after only a few changes.

[jason2459]

I only know of one tank that I would consider a successful system that has gone with out what most consider no water changes. As mentioned that would be GlennF's system as he's past the 10 year mark.

Many consider 1-2 years successful. I do not so that is all personal interpretation of what success is.

Most successful tank I know does periodic water changes which would be PaulB's going over 40 years now.

Even GlennF's system needs salinity adjustments because of skimmer, maintanence, coral fragging, etc where small amount of saltwater is removed over time. Some may consider that a type of water change, I wouldn't.

Otherwise, unless in a heavily drought stricken location, I see no reason to not do water changes. In those locations I wouldn't have a large tank and would have a glass top to reduce evaporation as well.

Water changes are a good way to remove things you don't want and can't easily or practically test for and a very easy and cheap way to import stuff you do want and also may not be able to easily or practical to test for.

http://reefkeeping.com/issues/2005-10/rhf/