Does activated carbon remove anything that I need in my aquarium?

w2inc · Jul 14, 2018

I got my ATI ICP test back and my water is high in the following areas:

Sulfur 1222 mg/l
Tin 6.01 µg/l
Iodine 530.5 µg/l
Aluminium 0.69 µg/l

Following actions should be applied in order to provide a stable water quality:
change 3 x 20 % of water (weekly cycle)
use carbon (50 g/ 100 l))

Which of these factors is carbon supposed to address? What else will carbon remove that I might need to replace after I start using it? How concerned should I be that I will clarify my water resulting in better light penetration that will burn my corals?

The tank is a 120. I don't and haven't used carbon, I don't change my water, no filter sock. I set up with ocean water. I use GFO, a protein skimmer, a version of an algae scrubber. I keep Live rock in the sump and moved from manual dosing to a calcium reactor 3 months ago. I believe my sulfur is high from dosing magnesium sulfate in the past. I also feed a considerable amount of dry food to about 40 fish living it it.

The tank housed an octopus for 6 months before being converted to a coral tank 10 months ago. I let it sit for about 3 months with window light and no livestock while some additional rock was seeded and my pod population grew. I have a nice plankton/pod culture in the tank. Coral and fish appear generally healthy. Some SPS do better than others. I would love to hear some thoughts.

Randy Holmes-Farley · Jul 14, 2018

Let's back up. Their recommendations are not always desirable.

Unless you have been using large amounts of Epsom salt for magnesium, the sulfate/sulfur is likely from your salt mix, so a water change will not correct it, and there's little evidence that it is a problem. That said, yours is pretty high. What salt mix?

The tin is probably not high enough to be a problem, but lowering it is a fine plan. It may be from your pipes, the glass, or a metal part in contact with the water.

Do you really mean 0.69 ug/L aluminum? If so, that's no concern.

The iodine is pretty high. Are you dosing it?

w2inc · Jul 14, 2018

Thanks Randy,

I was using a considerable amount of magnesium sulfate before read your article on DIY magnesium. Then I used other additives. I would feel comfortable thinking it was that. I believe that the tank got some Red Sea salt mix, but it would have been more than 16 months ago.

I was dosing iodine. I was not checking those levels regularly. I have stopped that.

I cut and pasted the levels, so I am sure that they are what was reported to me.

w2inc · Jul 14, 2018

Thanks Randy,

I was using a considerable amount of magnesium sulfate before read your article on DIY magnesium. Then I used other additives. I would feel comfortable thinking it was that. I believe that the tank got some Red Sea salt mix, but it would have been more than 16 months ago.

I was dosing iodine. I was not checking those levels regularly. I have stopped that.

I cut and pasted the levels, so I am sure that they are what was reported to me.

w2inc · Jul 14, 2018

Thanks Randy,

I was using a considerable amount of magnesium sulfate before read your article on DIY magnesium. Then I used other additives. I would feel comfortable thinking it was that. I believe that the tank got some Red Sea salt mix, but it would have been more than 16 months ago.

I was dosing iodine. I was not checking those levels regularly. I have stopped that.

I cut and pasted the levels, so I am sure that they are what was reported to me.

w2inc · Jul 14, 2018

I was using large amounts of magnesium sulfide. I now have Dolomite in my calcium reactor.

I was dosing iodine and have stopped.

I use Red Sea and mostly ocean water when I set the tank up.

I cut and pasted my results, so the levels are correct.

Thanks for the quick reply.

Randy Holmes-Farley · Jul 14, 2018

My recommendation is to continue regular water changes, nothing special. Stop the iodine and Epsom as you have. Nothing else is needed, IMO, and activated carbon, while fine to use, is unlikely to lower the iodine or sulfate , and the others are not best treated with GAC anyway.