When do I need to water change given parameters?

[Ballyhoo]

If my Ca+ is 440, phosphate.03 and nitrate is low (Salifert show very mild pink) when do I need to water change? Kh is like 6. i'm constantly testing because I have a couple coral like a $600 acantho and $600 HG Torch.m and several other lesser expensive but not cheap corals. even with all my good parameters once in a while I lose a species.

 

[jsmkmavity]

Im a big fan of regular consistant water changes, weekly or bi-weekly. Opinions will vary.

 

[Tahoe61]

Are you dosing anything?
If it were my tank I would do a modest water change.

 

[Ballyhoo]

Im a big fan of regular consistant water changes, weekly or bi-weekly. Opinions will vary.

why?

 

[Subsea]

Your KH is low for a reef tank.

What is your reasoning to not perform water changes, until problems develop?

 

[Mr. Mojo Rising]

why?

My answer (speaking only for myself) is that water change removes much of what we can't test for, and replenishes much of what we can't test for. We can only test for 6-7 parameters, but there is so much more in the water that we can't test, consider the icp test for example.

 

[Subsea]

My answer (speaking only for myself) is that water change removes much of what we can't test for, and replenishes much of what we can't test for. We can only test for 6-7 parameters, but there is so much more in the water that we can't test, consider the icp test for example.

Kudoes to your post.

The exudates of photosynthesis are DOC (Dissolved Organic Carbon) and that fuels bacteria growth. Depending on the ecosystem, that also fuels opportunistic algae growth.

 

[Troylee]

To remove doc’s and replenish traces… plain and simple!

 

[Subsea]

@Ballyhoo

“i'm constantly testing because I have a couple coral like a $600 acantho and $600 HG Torch.m and several other lesser expensive but not cheap corals. even with all my good parameters once in a while I lose a species.”

After 55 years of reefing, I no longer test and I keep cheap corals that display nicely. I also have too many tanks and I don’t perform regular water changes. Once a year, I perform three 50% water changes in one week.

I suggest you consider doing more water changes and test less.

PS: Dirty glass & diatoms on sand bed, normally get cleaned up before pictures.

 

[Randy Holmes-Farley]

I change water because of things I cannot or do not measure. Organics, for example, as well as tugging all elements toward the starting salt mix.

 

[Anna K]

I change water because I was told to. For my 40g I do 10% every week. I plan to move to every other week or so probably around the year mark. I know some people hardly do water changes, if any, but that's because they have an extremely mature system.

 

[Ballyhoo]

Great this is all informative. I'm just asking a question why and I'm happy that people are answering.

 

[jsmkmavity]

It helps export the unwanted and import what is depleted. If nothing else it will reduce the yellowing of your tank water (from fish waste and other things) and help keep stable parameters.

 

[jabberwock]

I do micro daily water changes to replenish what gets used up, and remove excess nutrients. About 30 ounces new water in, and 30 ounces new water in unless I need to adjust a little bit for salinity. I used to dread doing the obligatory 10% weekly water change.