Why are 100 percent water changes bad for sps systems

[brad65ford]

This has been spinning in my head for awhile now and hopefully there is some answers on this since it could really changed the success for sps'ers.

With having a smaller system its much easier to do 90-100 percent water changes as we call can a test too. But is it good and or does it shock the corals (sps's) and if so how come? Is it because its nutrient pour (po4/n03) or no bacteria flock? Now if its either or both, wouldn't there be something we can add to new salt water mixes? Guess i'm asking for the holy grail of answers because if there was a set formula or solution(s) to add it would sell like no tomorrow. Also since there isn't anything like this then that means we as hobbyist have no idea what these corals specifically need LOL.

 

[Reefvet]

Have you read this ?

 

[rynoe]

A healthy system is not so much based on the actual levels of the parameters but more so stability. High alk for example is not going to harm corals all that much. Dropping the alk down to the desired level rapidly however will likely do a great deal of damage. So basically YES it shocks the corals. On a side note it took me roughly six years to figure out that less is more in this hobby. I basically have never paid less attention to my tank as I do now and it has never been healthier. I basically just do a small weekly water change and monitor parameters, no additives or supplements or fancy methods and I currently need to stop my sps from growing so fast.

 

[cugly]

A healthy system is not so much based on the actual levels of the parameters but more so stability. High alk for example is not going to harm corals all that much. Dropping the alk down to the desired level rapidly however will likely do a great deal of damage. So basically YES it shocks the corals. On a side note it took me roughly six years to figure out that less is more in this hobby. I basically have never paid less attention to my tank as I do now and it has never been healthier. I basically just do a small weekly water change and monitor parameters, no additives or supplements or fancy methods and I currently need to stop my sps from growing so fast.

so you're saying you're not dosing alk or calcium or anything else and your parameters stays stable with a small weekly water change and with rapid great growth ..would love to see some pics and more details on your set up...

 

[rovster]

We have a local reefer aka SPS expert that does like 90% water changes on a huge system. He uses NSW though, so levels are probably very consistent. I think the biggest challenge is matching the parameters with that large a volume. If they are perfectly matched, or near perfect, then theoretically there should be no issues with a huge water change.

 

[brad65ford]

Define parameters. If your referring to the popular 3 (alk/cal/mg) that would be to easy. I believe bacteria, nutrients and n03/po4 may play a bigger role and impact the corals. This is something not talked about. We all know doing a certain percent of water changes are good for a running system since it removes wast and balance the ions etc etc. But we never talk about huge or large water changed since if that was all it took for successful sps system everyone could just do a large water change and your corals would be perfectly happy. I'm not sure if my question is coming across right which I may not be explaining correctly. What I'm trying to say is I bet there is something we can add to freshly mixed salt water for large water changes. This maybe why nsw large water changes are so successful they have everything in it (po4/no3/other nutrients) and no waste,,, while with in reason

 

[rovster]

Parameters: Salinity, Temp, Big 3.

If you are doing regular large water changes, then it would be difficult to shock anything with a change in nitrate or phosphate, assuming you have those levels within reason. I would routinely do 50% changes in my 14gallon without issue, sometimes even more.

 

[brad65ford]

Parameters: Salinity, Temp, Big 3.



If you are doing regular large water changes, then it would be difficult to shock anything with a change in nitrate or phosphate, assuming you have those levels within reason. I would routinely do 50% changes in my 14gallon without issue, sometimes even more.

Do you mean 2?
My bad, I automatically look past the obvoius at times since I test any new bucket of salt and the weight my salt for specific gravity. Temp's are always perfect do to house temp. Those should be no brainers and why its not mentioned though its important, the others i have listed imo are more difficult to control especially nutrient/bacteria levels.

 

[rovster]

Big 3, Cal Alk Mag. There is not a lot of free floating bacteria. Goal of WC is to reduce nutrients and replenish all the other stuff. Maybe you are overthinking?

 

[brad65ford]

When you run a extremely low nutrient BB system this can be an issue.

 

[Reefvet]

Define parameters. If your referring to the popular 3 (alk/cal/mg) that would be to easy. I believe bacteria, nutrients and n03/po4 may play a bigger role and impact the corals. This is something not talked about.

What other parameters would there be ? :eek2:

Changing water doesn't impact essential bacteria. The free swimming bacteria are not supporting your reef.

I think you need to do a lot more reading.

Here's a good thread to start with.

 

[Reefvet]

We have a local reefer aka SPS expert that does like 90% water changes on a huge system. He uses NSW though, so levels are probably very consistent. I think the biggest challenge is matching the parameters with that large a volume. If they are perfectly matched, or near perfect, then theoretically there should be no issues with a huge water change.

And no advantage either.

I've been using NSW for 20+ years. I can get all I want for free and I change 1% of water daily.

Read the linked article by Randy.

 

[rynoe]

Cugly, I should clarify that I run a calcium reactor so alk and calcium are being added. I was more referring to all the supplements and vitamins and special coral foods that are on the market when I said I was not dosing anything.

 

[brad65ford]

What other parameters would there be ? :eek2:

Changing water doesn't impact essential bacteria. The free swimming bacteria are not supporting your reef.

I think you need to do a lot more reading.

Here's a good thread to start with.

I have read this too that the bacteria in the flock is very minimal and also seen test results supporting it as well. I forget the article but it was referring to how much bacteria in one grain of sand versus what is floating in the water. But not the main point just grabbing individual things that we can reference may be different from a new 100 percent water change.

Good thread drop indeed and I have follow it as well. There are tanks that have such high p04/no3 it would make a great argument for those that want their p04/no3 to be closest to 0. Personally i have experiences it first hand how easy it is to strip the nutrients from a system especially when running a BB system, doing large often water changes with not much feeding. So it brings me back to the point I'm trying to make. What would you need to aid to a fresh salt water mix to make your sps's happy if you did a 100 percent water change. Time with feeding again or none of the above?

 

[rovster]

And no advantage either.

I've been using NSW for 20+ years. I can get all I want for free and I change 1% of water daily.

Read the linked article by Randy.

Never claimed it was advantageous, just posted the reference to show it can be done. We all have our ways and methods. Just trying to answer OP's initial question.