Poly Filter/Copper


New member
Help please. We had a brass fitting in the water below the tank (don't ask lol) for about a month. Everything died except the fish. So I just found out about the copper. So we put a poly filter in and tested for copper. The copper test (salifert) came up zero and the poly filter has been in there for about 12 hours and has not changed any colors. Is this possible to have everything negative and still have copper in the system?


Mangroves are kool.
Once in the water always in the water so i would recommend QT your fish and washing everything else (tank,filers,etc.) in mularic (is that correct?) acid or a lot of bleach and water.


Staff member
RC Mod
That the polyfilter hasn't turned is encouraging. Give it another few days. Run some carbon.

The problem is, it may also have killed the microscopic bacteria in your sandbed and rock. It may NOT, however, have reached below the surface, so bacteria will start re-colonizing the upper layers of sand and rock.
Treat it as a new tank, one in which you unfortunately already have fish. You don't say whether you have a filter on this system. But start testing for ammonia and nitrate, and have some Amquel on hand in case you get an ammonia spike. Feed lightly, and try a couple of snails. If they survive, add more snails/hermits until you have one per gallon. I am assuming you have 1 lb sand per gallon and 1 lb live rock per gallon: sand is somewhat optional, but the live rock isn't. Advise us if this is not the case and we will devise a plan.
Wean it slowly off the filter if this is to be a reef. Filter ok if this is fish-only.
Keep adding to this thread to keep it active and post your general parameters and tank description for more help.


New member
I am going to check parameters this morning. We have about a 3" sandbed and about 100lbs of LR (75 gal. tank). All inverts are dead except a few token crabs. Most coral is dead or close to dead...fish are all ok, so far. No mechanical filter, just all the LR and sand, a good skimmer and refugium with sand, LR and cheato in it. Thank so very much for any help. I will post parameters in a bit.


New member
Are you sure your test kit is good? After verifying that....

No amount of "cleaning" will remove all copper from your tank, unless you throw away the sand, rock, etc. However copper can be removed from the water chemically. I never used polyfilters, but they are supposed to work. What I used in the past was CupriSorbâ"žÂ¢ from seachem. It changes color also when it has absorbed copper. It must be run for a number of months until it stops changing color. The copper has been absorbed into the sand, rock, even the glass can hold onto it. As the concentration in the watter is reduced it will be released from these substrates and absorbed by the media. It's a long process, but it works. After the bulk of the copper is gone, inverts can be added. just continue to keep the poly filter or cuprisorb running until it's no longer needed.


New member
Ok water parameters are in:
Temp 77.8
Salinity 1.022
Ammonia -- <.25 (lowest that it shows on Salifert kit, but looked like zero)
Ph 8.1
Nitrite 0
Nitrate 15
kH 8.6
Calcium 450
Copper 0
the Poly-Filter now after 14 hours is a pale blue gray.


Clowning Around
Doesn't copper bind with other materials and not stay in the water very long? The little remaining water-borne testable copper could have been absorbed by the poly filter resulting in an undetectable copper reading even though copper poisoning to the inverts has indeed occurred. Something similar happened to me several years back so that's why I say this.


New member
yes that makes alot of sense that is why I am not real worried about the negative reading on the copper test. I am more worried now about my SB and LR. I don't really want to toss 100lbs and start all over, and some say I gotta if I want a reef again and others say hang in there it will be ok.