Unacceptable Parameter Swings

[sluicebox]

How are unacceptable parameter swings defined? For example, my Alk may range from 160 ppm to 190 ppm between water changes every week to 10 days. I am assuming that these changes are gradual as I am not testing daily.

My Ca levels vary between 380 and 480 between water changes. I am dosing both Alk and Ca in small amounts hourly with dosing pumps controlled by a Reefkeeper Elite.

I continue to have problems with STN and read that parameter swings are a possible cause. I think my parameters are relatively stable but have no real guideline for evaluation. My parameters are always within recommended limits.

My LPS corals are not having any problems.....I just have the easy to raise SPS like like Montiporas but still can't seem to able to keep them healthy.

 

[Alabamareef]

How are you measuring your Alk? Usually it's measured in dKH or mEq/L. What test kit are you using? IMO salifert seems to be an industry standard although I know there are lots of great kits out there. Also what is your ph? Are you using 2 part? If your using 2 part how much are you dosing daily?

 

[Alabamareef]

Also biopellet reactors can strip out to much good stuff. Do you have a controll valve and is it dumping back into your skimmer before it gets in your DT?

 

[RacinRevo0818]

Not sure on that alk since I only a measure in dkh. But your parameters shouldn't vary that much if your dosing with a pump.. Have you checked your freshly mixed saltwater? Not knowing size of system is also hard to tell. Nothing should be stripping alk and calcium from your system except for corals. Maybe watch bulk reef supply vid on dosing pumps makes it pretty easy to understand. I always have 2 different test kits for my alk, cal, and mag just so if one number is way off I can confirm with another test kit.

 

[SamsReef]

there are four parameters IMO which takes a toll on the corals. Between water changes, i try to keep between the following parameters:

temperature (within 2 degrees)
alkalinity(within .5)
PH (within .1)
salinity (within .01)

not to say it will kill the corals beyond that but these are what i target for.

 

[beaslbob]

How are unacceptable parameter swings defined? For example, my Alk may range from 160 ppm to 190 ppm between water changes every week to 10 days. I am assuming that these changes are gradual as I am not testing daily.

My Ca levels vary between 380 and 480 between water changes. I am dosing both Alk and Ca in small amounts hourly with dosing pumps controlled by a Reefkeeper Elite.

I continue to have problems with STN and read that parameter swings are a possible cause. I think my parameters are relatively stable but have no real guideline for evaluation. My parameters are always within recommended limits.

My LPS corals are not having any problems.....I just have the easy to raise SPS like like Montiporas but still can't seem to able to keep them healthy.

I highly suggest you read and implement the randy holmes-farley improved diy 2 part.

See:

https://www.reef2reef.com/forums/reef-chemistry-forum/39332-do-yourself-two-part-links.html

the variations you measure are very common with a water change system.

IMHO what you need to do is add calcium/carbonate/magnesium as they are being used up.

so the system tells you what it needs and you provide those things.

my .02

 

[sluicebox]

How are you measuring your Alk? Usually it's measured in dKH or mEq/L. What test kit are you using? IMO salifert seems to be an industry standard although I know there are lots of great kits out there. Also what is your ph? Are you using 2 part? If your using 2 part how much are you dosing daily?

The Hanna Alk meter reads in ppm. Easy conversion to dKH - multiple by 0.056 So, dKH runs from 9 to 10.6. If wanting to use mEq/L, you can multiple by 0.023. So, the range is from 3.68 to 4.37.

I use Salifert kits for Ca and Mg. Hanna for NO2, Alk, and Phosphate. Red Sea for NO3.

Dosing with BRS 2 part 75 ml/day of each. No need for to dose Mg as it is always pretty high (1400-1500 ppm) without any dosing.

 

[sluicebox]

Also biopellet reactors can strip out to much good stuff. Do you have a controll valve and is it dumping back into your skimmer before it gets in your DT?

Yes, I have a ReefDynamics Biopellet Reactor cut down low for the effluent. It dumps out into the reactor.

 

[sluicebox]

And the tank you've got is bad _ _ _!! Did you buy it new?

Yes, I bought it new back in May. I think it has been set up long enough for me to begin growing SPS but I'm having issues with the STN. My Zoas, Frogspawn, Hammer and Brain Corals look great.

 

[sluicebox]

there are four parameters IMO which takes a toll on the corals. Between water changes, i try to keep between the following parameters:

temperature (within 2 degrees)
alkalinity(within .5)
PH (within .1)
salinity (within .01)

not to say it will kill the corals beyond that but these are what i target for.

Thanks, I really appreciate your tolerance ranges. You're the first one to really answer the original question posed.

 

[sluicebox]

I highly suggest you read and implement the randy holmes-farley improved diy 2 part.

See:

https://www.reef2reef.com/forums/reef-chemistry-forum/39332-do-yourself-two-part-links.html

the variations you measure are very common with a water change system.

IMHO what you need to do is add calcium/carbonate/magnesium as they are being used up.

so the system tells you what it needs and you provide those things.

my .02

This is basically the same as the BRS 2-part dosing regime which I am following. But, I am changing salt mixes. I previously used Rea Sea Coral Pro salt and the parameters on the freshly mixed salt water are pretty high, especially for the Alk which is designed to be at 12.2 dKH. Since I am running the biopellets, I want that lowered to around 8. Therefore, I switching to Red Sea's Marine Salt which is much lower dKH and Ca.

Thanks for the reference to the article.

 

[Alabamareef]

What's your light cycle. I take it you've got the fixture that comes with the tank, 8 bulb T5. Where are you dumping your 2 part in at?

 

[Alabamareef]

Also why are you changing water weekly? A Is it RODI with 0 TDS?

 

[Alabamareef]

Also what are your Nitrates and your phosphates?

 

[sluicebox]

Also what are your Nitrates and your phosphates?

My original question was what parameter variations are considered acceptable in your opinion...not a diagnosis of my problems.

 

[Giancarlo]

My ALK varies by .5 dkh - as stated above there are a few ways to measure ALK.

I have not had issues with this fluctuation. When I have had big ALK swings for whatever reason, RTN or at least some sort of bleaching started, usually with birdnest type sps. Once ALK was dialed in the spreading stopped.

I don't think your swing is too much, but the problem might be that as it gradually is absorbed it is a small change, but once your doing the water change the big jump back up is likely the shock.

Your calcium varies way too much, In my opinion. Calcium on my system ranges from 420 - 440 ppm.

Ph I wouldn't worry on that, just because it naturally changes all the time. I would just keep an eye on the range.

 

[gmoney243]

hey bob just seen ur post here. yes alk swings of 9-10.6 in a week is to much you really need stable params for sps. try to dial in your dosing pumps to get a more consistant alk reading and use a lower alk salt such as red sea regular. also weekly water changes arnt needed unless your using it for nutrient control but your params are all in normal range so i would switch to monthly waterchanges unless you just want to do them weekly. either way try get a salt that matches params your running.

 

[Alabamareef]

Sorry Bob just trying to help. Been using 2 part for several years on a dosing pump and my levels range from Ca 460-480 and Alk 9.6-10.0. I've had good results with SPS. Good Luck