Large Tank Water changes

[HighDefAquaria]

Hello,

I currently run two systems—a 45-gallon and a 50-gallon—and perform weekly water changes on both. I’m considering upgrading to a 150-gallon tank and wanted to ask for some guidance. How often should you perform 10% water changes on a larger system?

I’ve always heard that larger tanks tend to be more stable. Assuming I will be dosing both major and minor supplements, what would be considered a healthy water-change schedule for a system of that volume?

 

[Elevated Ecosystems]

Hello,

I currently run two systems—a 45-gallon and a 50-gallon—and perform weekly water changes on both. I’m considering upgrading to a 150-gallon tank and wanted to ask for some guidance. How often should you perform 10% water changes on a larger system?

I’ve always heard that larger tanks tend to be more stable. Assuming I will be dosing both major and minor supplements, what would be considered a healthy water-change schedule for a system of that volume?

Usually biweekly

 

[Malum Argenteum]

How often should you perform 10% water changes on a larger system?

Depends almost entirely on bioload, species of inhabitants, and additional nutrient export practices.

 

[Ziggy17]

You’re not going to get a definitive answer on this question. If you don’t mind doing them, and you can afford the salt, it opens up the option to do weekly. But moonshiners will say it’s a placebo. They might be correct. My opinion is beginners Will likely be more successful with water changes. Only because we tend to make more mistakes and water changes help correct them. As you become a better reefer, less is probably ok. Perhaps you move to none.
But Again, no definitive answer.

 

[Marco_99]

I used to do weekly on over 100 gal but do biweekly now. My reasoning is when you are dosing elements and say kalk that pulling 10- 20 gal a week is probably rocking the boat more than helping the cause. It’s too short of time span for that much disruption. Plus I use a fairly spendy salt so I’d rather get a bit more mileage out of my bucket.

 

[Grog]

I try to keep to a schedule, but life happens. I try to do "Wednesday Water Changes". I mix up 12 gallons of water. I do a 4-gallon change in my 40 and an 8-gallon change in the 180.

Why? There is very little science here. I do this because I have a 12-gallon trash can to mix my water in, and its easy measurements. 6 cups of salt in 12 gallons of water, and I have 4-gallon buckets to divide it all after the mixing cycle. Why Water Change Wednesday? Well, it sounds cool, and is easy to remember, and I don't work the day job on Wednesdays.

In reality, I don't hit my weekly goal. Sometimes, it drifts to 10 - 14 days but I try hard to keep it at 7. IMO the 40 needs that 10% change and the 180 does fine with the 4% or so I'm changing. Either tank does better when I'm on the 7-day schedule. The water is clearer, there is less nuisance algae, etc. It is noticeable to me from visual aspect, so I do this.

I only do larger water changes in either tank when there is a problem. Like a dead fish that wasn't noticed, salinity out of whack, or an anemone going through a power head kind of event.

Not saying this is 'the way' but this is what I do and it works for me.

 

[HighDefAquaria]

I used to do weekly on over 100 gal but do biweekly now. My reasoning is when you are dosing elements and say kalk that pulling 10- 20 gal a week is probably rocking the boat more than helping the cause. It’s too short of time span for that much disruption. Plus I use a fairly spendy salt so I’d rather get a bit more mileage out of my bucket.

I recently switched to Aquaforest Reef Pro+ salt. With two other reef tanks and a third on the way, I’m trying to keep both cost and labor limited to what’s truly necessary. I know toxin export is one of the main reasons for performing water changes, but I assume a larger water volume is less temperamental.

 

[HighDefAquaria]

I try to keep to a schedule, but life happens. I try to do "Wednesday Water Changes". I mix up 12 gallons of water. I do a 4-gallon change in my 40 and an 8-gallon change in the 180.

Why? There is very little science here. I do this because I have a 12-gallon trash can to mix my water in, and its easy measurements. 6 cups of salt in 12 gallons of water, and I have 4-gallon buckets to divide it all after the mixing cycle. Why Water Change Wednesday? Well, it sounds cool, and is easy to remember, and I don't work the day job on Wednesdays.

In reality, I don't hit my weekly goal. Sometimes, it drifts to 10 - 14 days but I try hard to keep it at 7. IMO the 40 needs that 10% change and the 180 does fine with the 4% or so I'm changing. Either tank does better when I'm on the 7-day schedule. The water is clearer, there is less nuisance algae, etc. It is noticeable to me from visual aspect, so I do this.

I only do larger water changes in either tank when there is a problem. Like a dead fish that wasn't noticed, salinity out of whack, or an anemone going through a power head kind of event.

Not saying this is 'the way' but this is what I do and it works for me.

That’s definitely more inline with what my logic is. I’m also looking to do an Auto water change on this system to help in the effort.

 

[Grog]

That’s definitely more inline with what my logic is. I’m also looking to do an Auto water change on this system to help in the effort.

That would be nice but no auto-changer here. I keep a pump in the sump on a separate switch, so I just click it on to pump out 8 gallons, shut it off, and dump 8 gallons back in. Fairly easy.

Anything that facilitates your water changes, makes them easier, or motivates you to do them is good IMO. So, if it is a pump like I have, or an auto changer like you are looking at, all good. I think stability and regularity are the keys. The biology adapts to the situation and if you are on a schedule, then things are better.