100% Water Changes

Malenurse

Premium Member
I just read this advice from a very experienced reefer (marine biologist and author):

"In a nano, you shouldn't worry about phosphates or nitrates. Why? Because you should be draining that sucker empty and refilling it once a week! 100% weekly water changes for the win - best piece of advice Anthony Calfo ever gave me for my nano (over beers, nonetheless...)."

I was amazed by this and I'd love to hear if anyone out there uses this method.

Chris
 
I wouldn't fully support it. Using that seems to be a big punch to the tanks biological cycles. I would see 75 or 80% changes more reasonable. - Black_Majik

( I am writing on my co-workers account)
 
I do about a 40% weekly and believe me it's plenty, my P04 is at .002 ppm using a Hanna Colorimeter at that rate without the use of a skimmer...changing out 100% all the time wouldn't be wise in my opinion, it would prolly wreack havoc on your biological processes
 
Assuming the pH, temp and salinity were matched I suppose it would work, but why bother :confused: ?

If your water quality is degrading so much that you need to do 100% water changes weekly there are other issues you need to deal with.
 
I do a 1 gal every 3 days on a 6 gal nano with 20lbs of sand and a 15lb rock. so actually there s about 3 gals of water :-) and my tank LOVES me :-)
 
i do 5 gallons on a 24g nano once a week and i think that's more than enough. i'm actually gonna cut it back to once every other week. i feel the more established your tank is, the less you really need to do water changes. you wanna keep things stable and changing that much water is going to cause a lot of fluctuations i think.
 
hey remember that their are natural reefs out in the ocean that during low tide are completly exposed out of the water. as far as i can tell as long as you do not let the corals dry out and you dont have any kind of fish in the tank it should work vary well to your corals benifit. just be sure to not take or replace water to fast the last thing you want to do is mix thigs up and suck out the bio bacteria you have in your sand or growing anywhare lose.
 
Ive never heard of such a thing. I would never recommemd that unless your water is so messed up your corals are dying. Even then I wouldnt do a 100 percent change. I have a 25g and do a 3g change once every week or other week .

Have you tried this method yet? I would love to hear the outcome
 
hmm that sounds like a good idea but slow replace water, i got it set up a tank that has a slow drip taking water out of the tank then do the same thing with water coming in, but i can only see this working in a small tank no bigger than 5 gallons, does everyone get what i just said.

i mean in nature you never have to eplace water because it always replaces its self so do the same in a tank add ne water slowly and take out old water slowly, but that 100% doesnt sound like a good idea like said above to much stress on the fish
 
Yes

Yes

I never write brief and I hardly double space, sorry. :)

I am 1000% positive it works because I've been doing it for 9 years now. My current pico just hit 2.5 years on this approach, it's purple to the core and packed with corals as much per square inch as any large reef tank. The changes help, not hurt, and are a requirement for the way I pack corals into picos. I just match all the params and dump in the water, corals are opened up happy in 15 minutes every time. They get used to it quick. Most all the bazillion threads I've ever written about picos eventually wind up with this water change theory/practice, and I would also point back to work done on this site in the magazine I believe sometime in '04 that showed 20-30% changes don't do anything but accumulate wastes, which there is no room for in a pico. Larger tanks, and skimmed tanks, are more forgiving that's why so many get away with low level changes. My observations are anecdotal and centered around my low NO3 levels, I experimented with the change frequency to keep me under 15ppm and that amounted to bi-weekly 100%'s...but in this study they showed larger changes are needed, in the order of 50% iirc. I don't have to do it weekly, but I have had picos that did need it. my 1.5 gallon reefbowl gets this bi-monthly. The .5's got it weekly, when there was so much coral every square inch was comprised of living matter (that requires feed) along with shrimps and stars...

100% changes have nothing to do with poor design or quality approaches, they are designed to allow you to feed your system well instead of starving it and making corals live on their own energy stores as photosynthesis keeps them steady state for a while. By feeding well we can deliver the aminos, vitamins, proteins etc, so a pico reef can actually live longer than 3 months and be *growing* not just sitting there in near-starvation mode. Without feeding, the system gets stressed over time and will not thrive long term, although this cuts down on change needs. a non-fed system will not last years, period. Years should be the goal of any tank, and it's only my opinion the tank will go eutrophic in ~6 months if you don't change water aggressively. I guess it's possible to not do that and feed very lightly to prevent OTS in picos, but I'm not seeing any packed-tight picos living very long with the caloric-restriction or lax change approach.

I am absolutely certain it does not affect biofiltering, you have to give those little guys more credit than that!! I'm not being argumentative I'm just singing the praises of how this approach lets you pack corals into your tank in a ridiculous manner. Considering in a sporulated state 'somonads and 'bacters can live in your eyebrows, an oily puddle in the road or inside your microwave while it's being used, a few aggressive water changes simply do not affect these little ubiquitous wonders. They are bullet proof practically unless you zap em with antib's.

We wouldn't have algae problems in larger systems if changes were this aggressive, and it'd let you get away with a whole lot more feed which better represents nature anyway. Obviously it's not practical in large tanks, but in nanos, go for it and feed better than you currently do.
 
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Hey good comment about fish, not something I have to concern about in pico reefs. That very well may be of concern in larger setups, but if I had that issue I'd simply still do 100% changes and slowly exchange the water vs the mad ripping I do in the coral only systems.
 
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lastly, I don't want to preach how often one should change even if they do choose this method. Just test for nitrates, look around to find out what successful tanks have as an upper limit, and change as often as it takes to keep it there. Mine do well at 10 or less ppm (no algae)

I also suppose you could do many small changes as well to get the same effect? I just don't have time, so I rip it all out at water change time to buy me the most holdover until the next round!
 
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one other thing...I employ 100%'s as well to *proactively battle eutrophication, the #1 enemy of long term pico reefs. The day you increase water changes in relation to you seeing a new strand of hair algae is the day you should have been doing power 100%'s for the last several changes.

Never *react* to algae in a pico, at that point just start over.
You do whatever extreme it takes to prevent them from ever showing up, or like a woman you can't trust you'll be on the trail behind it's progression forever. :)

Trust me you'll like this approach! I've lost a lot of early picos in becoming reactive so once again the 100%'s work well for picos I can say with pure assuredness
 
Brandon429 - two questions for you. You keep mentioning pico's which I assume is something less than 6g, do you think 100% will be ok in tanks in the nano range - 6 to 30g gallons? Second, are your tanks with sand beds or bare bottom and if you use sand do you vacuum the sand?
 
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thanks for the follow up. In picos I am meaning a gallon or less. I would have to extrapolate the same results to larger tanks, meaning if 100% doesn't hurt pico corals I don't see how it could hurt other systems but the fish angle was a smart concern. I do believe it would cost/hassle prohibitive to do it at 30 gallons, but if you did I can say your tank will not mind.

My systems were both, sandbedded and not. I ran the same changes in both systems. I don't vaccuum out the beds but every 3 months or so I suck up an inch off the top layer (wherever the detritus pockets form) and replace it with fresh sand, again as a proactive approach. in considering the differences in bedded vs non beds for some reason the vase reefs don't mind either way.

My 2 year old vase system (youtube/ reefbowl) has a 4 inch bed that gets light top layer changes occasionally and so did the reefbowl in my avatar pic that lasted almost 4 years iirc. Interestingly, that sandbed was never changed out nor disturbed one single time in years and years, so for that I thank the 100% change approach.
 
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you know I also didn't mention refugiums and other actions that can bind or export NO3 to reduce change needs. It's just obvious in tiny systems the simple approach may be best and provides the least weak links in the system, and many people with 6+ gallon nanos often choose the same bare-bones approach, this lends more credibility to the 100% mode but it is not the only way! Its just the easiest and most effective in tiny systems and in employing it for so long I'm sure it won't hurt larger ones should someone choose that approach.
 
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Reguardless as what size a tank one has and why one would change out 100% water. Lets discuss why it can not hurt a system to do a 100% water change. Many people have this notion that a bio filter has to do with the water and if you change out all the water you hurt the bio filter when in reality it has to do with the rock, sand and what ever else is in the tank that the bacteria can stick to. Branon429 - sounds like you know the science behind this, I just know the facts but I can't explain in scientific terms.
 
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That's a great statement, and exactly why you can run uV sterilizers if you choose and it doesn't kill your bio bed. Yes these bacteria are in water, but far more are found permeating the surface areas in the walls and decor and life. Those little creases and folds hold so much bacteria that if you rip it out of the water table in a giant water change, or kill it with high gamma irradiation, they just keep on trucking as I see it...

Regardless of if my diatribe is accurate or not, I thought it was cool to at least be able to say I have ran hundreds and hundreds of 100% changes exclusive to any partial changes and it has helped, not hurt, in the unique biochemistry of incredibly small and packed reefs. Go check the youtube vids I'm trying to increase my hit rates! :) lol
B
 
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