Parameter swings

[dbrown4183]

I have a 1.5 year old reef tank and my parameters are not not “stable”. I am getting the following fluctuations and am not sure how to either correct them or if they are close enough considering presently I see no effect on my coral. I will be honest I don’t know if it is growing at a rate it should or is colored as it should be but it looks healthy to me.
Tank size 120 gal with 80 gal sump
Temp 78.0 - 79.7F checked with probe
Alkalinity 8.1 - 8.7 checked daily
Density 1.024 - 1.026. Water change 3 gal daily with AWC
PH 8.1 to 8.3 checked with probe
Phosphate 0.01 - .15 checked weekly
Nitrate 5-20 ppm checked weekly
Calcium 380 -440 checked weekly
Magnesium 1200-1440 checked weekly

These are the maximum and minimums I realize the numbers are close to where they should be when looked at individually but are these too much of a swing in numbers?

Just trying to decide whether to panic or try to chill

Thank you for any advice

 

[rishma]

Chill

Most of those fluctuations can be chalked up to test error and/or natural variations during the day. A couple of thoughts…

What are you dosing?

What are you testing with?

Stop testing magnesium. Those kits are too inaccurate to bother with.

the only one I’d try manage more tightly is phosphate. 0.01 is a potential problem.

 

[BryanM]

I vote chill as well. Home test kits just aren't that accurate, at least not in my experience.

 

[Gumbies R Us]

I also wouldn't fall into the trap of chasing numbers. When you start chasing numbers, you can do more harm to your tank than good.

 

[Randy Holmes-Farley Verified Community Expert]

Aside from changes due to salinity changes by evaporation, there is not, IMO, anything problematically unstable in any reef tank that is not adequately dealt with by:

1. daily alk additions. If demand is more than 0.5 dKH per day, spreading the doses out over the course of the day may (or may not) be beneficial.

2. Daily and sometimes less often addition of calcium, in proportion to the alk dosed (not based on tests which are too variable for daily testing)

3. Weekly or perhaps even monthly dosing of magnesium in proportion to the alk and calcium dosed. Not based on testing./

4. Daily to weekly dosing of trace elements, if you are adding any.

 

[dbrown4183]

Thank you all for your help it is truly appreciated

 

[dbrown4183]

Chill

Most of those fluctuations can be chalked up to test error and/or natural variations during the day. A couple of thoughts…

What are you dosing?

What are you testing with?

Stop testing magnesium. Those kits are too inaccurate to bother with.

the only one I’d try manage more tightly is phosphate. 0.01 is a potential problem.

Thank you

I am dosing with All for Reef
Testing Alkalinity with Hannah and Hyros IV
Testing PH with Hydros probe and API
Testing Magnesium with Salifert
Testing Phosphate with Hannah ultra low Phosphate
Testing Nitrate with API
Testing Density with Refractometer
Temperature with Hydros probe and digital thermometer

 

[rishma]

Thank you

I am dosing with All for Reef
Testing Alkalinity with Hannah and Hyros IV
Testing PH with Hydros probe and API
Testing Magnesium with Salifert
Testing Phosphate with Hannah ultra low Phosphate
Testing Nitrate with API
Testing Density with Refractometer
Temperature with Hydros probe and digital thermometer

Great! When dosing all-for-reef there really is no need to test calcium and magnesium. AFR provides both in the correct proportions to alkalinity. Just dose enough to keep alkalinity reasonably stable and Ca and Mg will fall in line.

If I were you I’d feed more or dose phosphate to keep it from bottoming out. Otherwise I think you are in good shape.

 

[Randy Holmes-Farley Verified Community Expert]

I agree with Rishma and do exactly as he suggests.