When is too much 2-part?

[phillygeeks]

This is kind of a two part 2-part post. First is there ever a time where you are dosing too much 2-part? and the second is I feel like my tank is consuming too much likely due to excess abiotic precipitation/consumption, any thoughts on how I may reduce abiotic consumption?

57g mixed reef with small and moderate size frags, definitely not heavily stocked with corals
Dosing BRS 2-part with neptune DOS
6 hour intervals of alternating alkalinity and calcium
Current daily dosing is 156 mls of each calcium and alkalinity using @Randy Holmes-Farley recipe
Alk 7 - 8.5
Ca 420 - 480
Mg 1250 - 1350
pH 8.1 - 8.3
Do water changes every 10 days with RedSea Coral Pro
Sg 1.026 to up to 1.027 when i do a water change (part of my question of when is too much 2-part)
Nitrate 1
Phos 0.04
I notice a frustrating amount of clumping of the sand, it is CaribSea Arag alive
also a good amount of precipitation on the heater
That being said the consumption went up from approximately 100 mls of each per day to its current levels and it corresponded with adding more corals and better coral growth

 

[smpolyp]

If you feel you have to dose high amounts of a two part and are testing often then most likely you are correct on to much. Just remember we are shoving so many inhabitants in a small glass box we forget they need. They have the biggest resource in the world around them water. Increasing the water volume will increase the amount of elements available for your corals.
I also see you said "I notice a frustrating amount of clumping of the sand, it is CaribSea Arag alive" When the pH drops in the sand you will see it fuse together.
"also a good amount of precipitation on the heater" If the precipitation is high this could be due to the limitations of what the water can hold.

 

[Randy Holmes-Farley]

That is quite a large dose (4 dKH per day), but not above what soem folks use.

Do you see excessive abiotic precipitation other than the clumping??

 

[Randy Holmes-Farley]

Clumping of sand may be purely abiotic, but may also be driven by biological processes, and most often happens with new sand.

Reduced precipitation can be reached with lower pH, alkalinity and to a much smaller extent, calcium, and higher magnesium, organics, and phosphate.

Fresh CaCO3 surfaces can be most prone to more precipitation. To break the cycle, it can be useful to stop dosing for a few days, let alk fall and preciptitation stop, then restart with a much lower dose.

 

[phillygeeks]

That is quite a large dose (4 dKH per day), but not above what soem folks use.

Do you see excessive abiotic precipitation other than the clumping??

Just on the heater. I think at its peak I was having to clean my return and skimmer pump every few weeks. It has since reduced

 

[phillygeeks]

Clumping of sand may be purely abiotic, but may also be driven by biological processes, and most often happens with new sand.

Reduced precipitation can be reached with lower pH, alkalinity and to a much smaller extent, calcium, and higher magnesium, organics, and phosphate.

Fresh CaCO3 surfaces can be most prone to more precipitation. To break the cycle, it can be useful to stop dosing for a few days, let alk fall and preciptitation stop, then restart with a much lower dose.

Sounds reasonable. However, I am a bit nervous of letting the alk drop too low and its effects on the coral. I did a WC 2 days ago and alk was 8.2 dKh. I didn't check yesterday, but today it is already 6.9. Would holding dosing for a couple days potentially had an adverse affect if alk is already 6.9?

I do have to make up some new solution. Seems like it may be beneficial to use sodium bicarbonate instead of the sodium carbonate in that I would have a lower pH?

 

[jenreefer]

I am not sure I am following completely, but thought I would add that with water changes come differences in the amount of Alk and Ca that might need to be added to the tank. I have found that I have to add additional Alk to my tank to keep things stable. Do not forget to interpret the Alk and Ca of the newly added water as a source of the mismatch. I have talked to many who agree that the need for Alk is higher than the need for Ca due to inequities in newly mixed salt water.

 

[phillygeeks]

Thanks for the input! I am using RedSea Coral Pro salt. Per their website it should mix to an alk of 11.5 - 12.4 dKH, Ca 450 and Mg 1390. If my batch is truly similar that seems to be enough alk. Maybe even too much for my tank, given my precipitation problem

 

[jenreefer]

Thanks for the input! I am using RedSea Coral Pro salt. Per their website it should mix to an alk of 11.5 - 12.4 dKH, Ca 450 and Mg 1390. If my batch is truly similar that seems to be enough alk. Maybe even too much for my tank, given my precipitation problem

Point taken, seems that the alk in your newly mixed saltwater is high, so that may be a source of precipitation.

 

[Randy Holmes-Farley]

Sounds reasonable. However, I am a bit nervous of letting the alk drop too low and its effects on the coral. I did a WC 2 days ago and alk was 8.2 dKh. I didn't check yesterday, but today it is already 6.9. Would holding dosing for a couple days potentially had an adverse affect if alk is already 6.9?

I doubt it. Demand slows as alk drops, and 6.9 dKH is still a bit above natural levels.

Baking soda is a fine choice.

 

[phillygeeks]

Looks like switching to baking soda as a 2 part additive helped in reducing my alk/ca consumption by a factor of o.5 and I haven't had as much abiotic precipitation, which is great! Unfortunately, during the tuning with a couple days of alk dropping into the low 6's, I likely lost my garf bonsai and a couple other corals have stalled or regressed. However, things seem to have at least stabilized and some corals even seem to be picking up again with growth

 

[Randy Holmes-Farley]

Thanks for the update and sorry about the loses.