Phosphate buffer medium

[Dutch_Mill]

What medium would be the highest density (space efficient) medium to buffer phosphate in the way live rock does? I need something to stabilize my phosphate better without taking up the massive space live rock does. Preferably something like Maxspect bio blocks for easy cleaning and efficient stacking or something granulate.

Any suggestions? Would Rowaphos work? I remember reading articles once that it does leech back once the system has less phosphate than the media.

 

[Timfish]

All the biology in our systems are messing with phosphorus. Biofilms can significantly alter the sorbtion properties of the rock they cover and sponges can sequester phosphorus in crystaline forms. Feeding animals is obviously altering levels. Depending on the food webs in your system your corals could potentially be a source of PO4. Keep in mind hobbyest test kits and testers are only checking for the dissolved inorganic form PO4 (orthophosphate) and we can't test for the dissolved organic forms or for any particulate forms. If you are wanting to remove excess PO4 any of the GFO products like Rowaphos is a good way to do so however it needs to be monitored to avoid stripping out too much PO4 or making sure PO4 is not too high.


FWIW .03 mg/l is the threshold level to prevent phosphorus limitation in corals, identified by researchers at Southampton University in England using corals maintained in an aquarium for about a decade. .3 mg/l is what corals are subjected to with upwelling in the ocean. .5 mg/l might be acceptable for some as acros have been shown to increase growth up to this level. .9mg/l is the level the Steinhart Aqaurium's ex situ sexually reproduced acro colonies are being grown out with. Rich Ross's (who's part of the team at Steinhart) has his acro dominate mixed reef sitting at 1.8 mg/l, his tank can be seen at the beginning of his MACNA presentation on phosphate.


Fig 4 from this paper
https://esajournals.onlinelibrary.w...98e60zfBEvx5IcIVGhmlpUYmzIJuqUNVm0sG8_0vth6lq

 

[Randy Holmes-Farley Verified Community Expert]

What medium would be the highest density (space efficient) medium to buffer phosphate in the way live rock does? I need something to stabilize my phosphate better without taking up the massive space live rock does. Preferably something like Maxspect bio blocks for easy cleaning and efficient stacking or something granulate.

Any suggestions? Would Rowaphos work? I remember reading articles once that it does leech back once the system has less phosphate than the media.

The answer may depend on what level you want to stabilize at, but high surface area materials will be best. Fine calcium carbonate, and various types of GFO would all be candidates. I’d first try calcium carbonate since it clearly has decent binding in the concentration ranges we want. Either sand or coral skeletons, possibly ground up a bit.

 

[Dutch_Mill]

All the biology in our systems are messing with phosphorus. Biofilms can significantly alter the sorbtion properties of the rock they cover and sponges can sequester phosphorus in crystaline forms. Feeding animals is obviously altering levels. Depending on the food webs in your system your corals could potentially be a source of PO4. Keep in mind hobbyest test kits and testers are only checking for the dissolved inorganic form PO4 (orthophosphate) and we can't test for the dissolved organic forms or for any particulate forms. If you are wanting to remove excess PO4 any of the GFO products like Rowaphos is a good way to do so however it needs to be monitored to avoid stripping out too much PO4 or making sure PO4 is not too high.


FWIW .03 mg/l is the threshold level to prevent phosphorus limitation in corals, identified by researchers at Southampton University in England using corals maintained in an aquarium for about a decade. .3 mg/l is what corals are subjected to with upwelling in the ocean. .5 mg/l might be acceptable for some as acros have been shown to increase growth up to this level. .9mg/l is the level the Steinhart Aqaurium's ex situ sexually reproduced acro colonies are being grown out with. Rich Ross's (who's part of the team at Steinhart) has his acro dominate mixed reef sitting at 1.8 mg/l, his tank can be seen at the beginning of his MACNA presentation on phosphate.


Fig 4 from this paper
https://esajournals.onlinelibrary.w...98e60zfBEvx5IcIVGhmlpUYmzIJuqUNVm0sG8_0vth6lq

Thank you for this information. Will be reading more about the high nutrients.

That said, I am not looking to reduce phosphate. I dose phosphate. I am looking to stabilize the graph. Less quick raise/drops in values.

 

[Dutch_Mill]

The answer may depend on what level you want to stabilize at, but high surface area materials will be best. Fine calcium carbonate, and various types of GFO would all be candidates. I’d first try calcium carbonate since it clearly has decent binding in the concentration ranges we want. Either sand or coral skeletons, possibly ground up a bit.

Thank you for the reply. I would like to stabilize around 0.07 phosphate. If fine calcium carbonate is the best media for this I'll go for ground coral skeletons. Some bags of this stuff in the sump would be easy to clean from detritus as well.