Combining two tanks Chemistry questions

Ian Baxter

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I have two tanks, 60g and a 200g, that I am planning to merge all into the 200. The 60 is full of corals, mostly LPS (torches, chalices, scolima, favia), zoa's, a few Monti's, and 12 anemones. Both tanks have fish, 5 in the 60 and 8 in the 200. I'm not worried about the number of fish based on species. But I would like to move everything at one time, without acclimation, so the fish in the 200 do not have dominance. I will be using most of the water from the 200 along with about 45g fresh mixed Red Sea Blue bucket. Will use new sand and temp will be similar. My question is how close my parameters need to be at the time of combining them.

60g: 200g:
NO3 - 11.8 NO3 - 29.4
PO4 - .162 PO4 - .546
Alk - 7.5 Alk - 7.3
Cal - 480 Cal - 507
Mag - 1360 Mag - 1450
Sal - 1.026 Sal - 1.026
 

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I have two tanks, 60g and a 200g, that I am planning to merge all into the 200. The 60 is full of corals, mostly LPS (torches, chalices, scolima, favia), zoa's, a few Monti's, and 12 anemones. Both tanks have fish, 5 in the 60 and 8 in the 200. I'm not worried about the number of fish based on species. But I would like to move everything at one time, without acclimation, so the fish in the 200 do not have dominance. I will be using most of the water from the 200 along with about 45g fresh mixed Red Sea Blue bucket. Will use new sand and temp will be similar. My question is how close my parameters need to be at the time of combining them.

60g: 200g:
NO3 - 11.8 NO3 - 29.4
PO4 - .162 PO4 - .546
Alk - 7.5 Alk - 7.3
Cal - 480 Cal - 507
Mag - 1360 Mag - 1450
Sal - 1.026 Sal - 1.026
The only one I’d be concerned about would be the phosphate , personally I’d bring that .5 down to the 60 level
 

Randy Holmes-Farley

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CaribSea Arag-alive.

Although, the sand in the 200 is only about 2 months old.

One concern is how much the phosphate may drop when adding the new sand. The rise that the corals in the 60 might see is less concerning than a drop.

I expect all will be fine, chemistry-wise, though corals are often quite disgruntled by such a move.
 
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Ian Baxter

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One concern is how much the phosphate may drop when adding the new sand. The rise that the corals in the 60 might see is less concerning than a drop.

I expect all will be fine, chemistry-wise, though corals are often quite disgruntled by such a move.
My 60 is currently battling green dinos and some LPS are not doing great. Finally got the no3 and po4 stable.
 

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One concern is how much the phosphate may drop when adding the new sand. The rise that the corals in the 60 might see is less concerning than a drop.

I expect all will be fine, chemistry-wise, though corals are often quite disgruntled by such a move.
Do you know how reliant the phosphate binding of sand is on microbiological activity (causing local pH changes, etc.)?

I'm more or less in a similar situation (but with dry sand) and was thinking about "pre-saturating" it by letting it sit in a water bath with added phosphate for one or two weeks before adding it to the tank...
 

Randy Holmes-Farley

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My 60 is currently battling green dinos and some LPS are not doing great. Finally got the no3 and po4 stable.

Green dinos? I’ve not really seen any color but brown, but perhaps I’ve just not seen that type.
 

Randy Holmes-Farley

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Do you know how reliant the phosphate binding of sand is on microbiological activity (causing local pH changes, etc.)?

I'm more or less in a similar situation (but with dry sand) and was thinking about "pre-saturating" it by letting it sit in a water bath with added phosphate for one or two weeks before adding it to the tank...

Fresh calcium carbonate surfaces will bind phosphate directly, dependent of microbial activity. Bacteria covering the sand grain surfaces will deter phosphate from getting to it.
 

EnterName

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Fresh calcium carbonate surfaces will bind phosphate directly, dependent of microbial activity. Bacteria covering the sand grain surfaces will deter phosphate from getting to it.
Okay, then this could work in theory... still a somewhat unsettling experiment. I will verify on a small scale first before risking anything.

Thank you!
 

Randy Holmes-Farley

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It's a dark green that goes away at night and come back as the lights turn back on. It's a pain.

Have you identified it as dinos with a microscope?

I have red cyano that behaves that way.
 
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Ian Baxter

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Have you identified it as dinos with a microscope?

I have red cyano that behaves that way.
No I haven’t. I didn’t know canyo would go away and come back during the day.
 

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I was relying on the all mighty chatGPT and it said canyo and green dinos. 🤣. It did help me get rid on dinos in the past.
 

Randy Holmes-Farley

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I was relying on the all mighty chatGPT and it said canyo and green dinos. 🤣. It did help me get rid on dinos in the past.

Sounds sketchy. lol
 

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