Tank Parameters all over the place

I’ve done awc for years and years. It’s not for nutrient export really. Unless you have a smaller aquarium. I did it for trace elements. Just to constantly get a little fresh elements in there. So yeah. It’s not gonna help you much right now. Later when you’re using a lot of elements then it might be worth it. Cuz your aquarium is on the larger size. If you did 1-2 gallons a day. That’s nothing. You would be wasting your time and money.
 
Interesting, I checked a few posts on R2R where people do like 1% daily change and can swear by it.. is it is a waste of time given my nutrients level are so high that 10% wont help or in general anything less than 25% is useless?
Erin has an extreme position to water changes, and he has been successful with this for a long time (although he is not testing his water :)…). Also, keep in mind he is using natural sea water, which is in many ways quite different than the artificial saltwater we are using.

IMO, it is not useless to have a routine in doing water changes, small or large.

Reef Moonshiners will argue against any water changes, others will advocate for larger water changes. It is like some love using Kalkwasser, others not so much (but we will not get into this now :)…).

I am in camp water changes, and those who I listen to all do it, some of them have very large 300+ gallon fully stocked acro tanks.

The objective of water changes is also debated.

Some believe it is nutrient export, some believe it is trace element replenishment.

While both are achieved, I would never do water changes for trace element replenishment. Also, to have a meaningful replenishment, you have to do large water changes, specifically if you have a fully stocked tank, otherwise you are always behind the curve with water changes and having the traces in good ratios. It is not a worthwhile effort to target traces with this.

I believe in the nutrient export objective of water changes. So Erin is correct, the more the better - to an extent. You have 100 mg/L NO3, replace 10% of water, you have 90 mg/L of NO3. Still better than not doing it, but not a great improvement. There is a problem with doing 10% and ‘polluting the water’ but 10%+ week over week. So if it is enough depends on how much nutrients are getting into your water.

However, I have been doing for months 30-40% of weekly water changes (up to 50 gallons out of 150 gallon total water), in addition to a strong skimmer and GFO. Any my nutrients never dropped below 10 mg/L NO3 and 0.1 mg/L PO4, my target parameters, unless I am adding relatively heavy carbon dosing. In this case, I am able to drop NO3 below 10 mg/L, but not phosphate.

Why: Feeding too much? Many say this should not be considered or needs to be accepted. Too many larger fish, most likely. So my tank is not well balanced with fish and nutrient export, unless I am replacing 30-40% of the water. An expensive effort over time.

The other downside of larger water changes I am experiencing at the moment is the effect of the anti-caking agent which raises iron and manganese into very (!) high levels. This does not happen with natural sea water.

Therefore, I am currently experimenting with weekly water changes with not more than 20%, because my working theory at the moment is that it will give me very similar results (I did less than 30% in some weeks and saw very similar parameters).

Lastly, I am personally against Auto Water Changes. Too much equipment is involved which can fail, and cleaning ‘some parts’ of the sandbed on a regular basis and most importantly the sump gives much more bang for the buck than replacing relatively clear water - unless you have a bare bottom tank. In this case, it could make sense, but I would focus more on the sump - in fact, I clean my sump weekly and some parts of my sandbed once a month.
 
There are many levers to pull when reefing. The "water change" lever is a coarse-precision lever that generally pulls parameters towards the baseline, and thus can be a super useful and reliable tool. There's also other levers, like dosing, skimming, chemical absorbers, fleece rolling, etc, which can affect the tank. Some people choose to rely solely on a select group of levers and reject the others, which is fine.

The thing about doing water changes is that if you are doing them properly, it can only bring your water towards baseline, and is therefore generally "good enough" of a choice. You are just replacing water in your tank with water with parameters that are all within range (I guess N and P could be a problem if you are already bottomed out, but that's not an issue here).

Other methods are often more involved in terms of testing, monitoring, checking and tweaking.

I clean my sump weekly and some parts of my sandbed once a month.
I'm actually curious about this. What are you trying to remove from the water when you clean the sump and sandbed? What does that actually look like: are you removing sponges, mulm, etc?
 
The thing about doing water changes is that if you are doing them properly, it can only bring your water towards baseline, and is therefore generally "good enough" of a choice. You are just replacing water in your tank with water with parameters that are all within range (I guess N and P could be a problem if you are already bottomed out, but that's not an issue here).
this is the part I question though. It does not bring your parameters towards the baseline in many cases - directionally yes, but often does not offset consumption, i.e., for traces, so it is not good enough unless you have limited consumption aka growth, then it might work.

Same as for export, so in my nano tank, where parameters are often below 10 mg/L, 0.1 mg/L, I still do 30% water changes as it will only bring me down to 7 mg/L, 0.07 mg/L.

What I am trying to say is that water changes does not fix your export issue or restores traces, but it is more useful in the context of nutrients than it is in the replenishment of traces unless it is a beginner tank / low consumption low growth tank.
 
It is true that it won't restore traces or fully export your nutrients. Traces have to be supplemented and nutrients rely on other methods for export. However, it still dilutes possible toxins, metals, and other things that we don't test for or know about.
 
It is true that it won't restore traces or fully export your nutrients. Traces have to be supplemented and nutrients rely on other methods for export. However, it still dilutes possible toxins, metals, and other things that we don't test for or know about.
That's a great point (I forgot to mention). Another big benefit of water changes are the continous removal of unwanted organics, which we now can test for (MS Organo, Oceamo) to at least some extent (drugs in the water etc).

For that reason alone, i am surprised why moonshiners insist that no water changes should be done even though there is a strong chance that there are unwanted organics in the tank which are getting ‘controlled’ by continous dilution.
 
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I love reading different perspectives that have worked for different people.. Some are extreme, some are more conventional - but they all have worked for people sharing in this thread! There are definitely more than 1 ways to bell the cat, and this is just the start of my hopefully long reef journey where I am able to test all these different methodologies myself and learn.. no water changes appeal to me a lot - saves time, money and my back! But for now short term plan is to try something majority in this group suggested - change water often! Theoretically what @tribbitt said makes sense that water changes take us closer to the baseline, but there are definitely other factors that contribute to the high nutrients.. would love to come back to this thread in couple of months to say what Alex said earlier - I can swear by water changes; they do wonders!
 
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this is the part I question though. It does not bring your parameters towards the baseline in many cases - directionally yes, but often does not offset consumption, i.e., for traces, so it is not good enough unless you have limited consumption aka growth, then it might work.

Same as for export, so in my nano tank, where parameters are often below 10 mg/L, 0.1 mg/L, I still do 30% water changes as it will only bring me down to 7 mg/L, 0.07 mg/L.

What I am trying to say is that water changes does not fix your export issue or restores traces, but it is more useful in the context of nutrients than it is in the replenishment of traces unless it is a beginner tank / low consumption low growth tank.
It brings it TOWARD baseline, not TO baseline. It won't be enough for everything, but it's often helpful and rarely hurts to do. It brings it however many % closer to the baseline as you decide to change.
 
That's a great point (I forgot to mention). Another big benefit of water changes are the continous removal of unwanted organics, which we now can test for (MS Organo, Oceamo) to at least some extent (drugs in the water etc).

For that reason alone, i am surprised why moonshiners insist that no water changes should be done even though there is a strong chance that there are unwanted organics in the tank which are getting ‘controlled’ by continous dilution.

See how much dust settles onto an undusted surface in a month. And mystery chemicals that piggyback in on dirty hands or impure additives or trace metals in fish food or whatever erodes off of your algae scraper or pollen that has pesticides on it.

You don't need to know what's in your water to be able to rectify it just by doing a water change, which is the biggest thing for me.
 
For that reason alone, i am surprised why moonshiners insist that no water changes should be done even though there is a strong chance that there are unwanted organics in the tank which are getting ‘controlled’ by continous dilution.
Not entirely true, as there are those that run the moonshiners program and still perform waterchanges. The essence of it is stability, hence why there are daily doses of certain elements that are depleted quickly. I send in an ICP for each batch of salt I stock up on and do the corrective doses before performing a WC. Just my preferred method of nutrient export in addition to an algae reactor and CAC. For others running RMS, it means not changing the water at all, which of course comes with inherent risk.

To the OP, I recommend not to put any focus on trace elements at this time. You'd be focusing on getting 2% of your water right while the rest goes to crap. Find a salt that's close to what you wat to keep your tank at and go to town on multiple WC over the course of a couple weeks. There's not much I havent been able to resolve with a few good WC.

Your parameters will solve itself by doing so. So dont start going crazy dosing all sorts of stuff, you'd be wasting money.

Once your numbers are in line, take some time to get in tune with your tank.

1- stable salinity & temp
2- alk & alk & alk (not 3 different things, just stressing importance)
3- CA & Mg
4- nutrients (how much you import vs how much you export)

Some of the above you can keep stable by dosing, others, like nutrient balance, comes with time in developing your microbiome and a regular maintenance schedule to match your stocking level and feeding. I like the analogy of different levers that can be pulled by @tribbitt , and couldn't have put it better myself.

What you do and how you maintain will be entirely up to your system and what you feel is acceptable.

HTH
 
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