View Full Version : Any need to start dosing two part?

12/22/2011, 02:42 PM
Hey guys,

Have a 20 gallon nano with sps, and have recently noticed my corals are taking up alk, calcium, mag, and iodine.

Post water change I get:

Cal - 460
Alk - 8.5
Mag - 1380
Iodine - .09

One week after water change (i do weekly water changes) I get:

Cal - 450
Alk - 8.3
Mag 1350
Iodine - .06

I have started adding 1 drop of lugols weekly to take care of Iodine, but was wondering if I should start dosing a two part for Cal, Alk and Mag? Weekly water changes bring numbers right back up, but do the minor reductions throughout the week effect the corals at all?


12/22/2011, 02:59 PM
From the info on Randy Holmes has posted in the past, there is not an accurate test kit available to test Iodine in our water. Iodine is present in the weekly water changes and should be fine. I also have a nano like yours and I only do weekly water changes and all the parameters seem to stay about the same. IMHO those drops in value do not seem significant enough to warrant two part additions. In this small of a system, you can do more harm than good.

I have had the nano system for about 5 years now. IF you notice that your values are gradually dropping over a couple of months period, then maybe add two part.

Two part system from Bulkreefsupply.com has worked for me in the past. They actually have a calculator to help you adjust the values slowly.

Hope this helps

Randy Holmes-Farley
12/22/2011, 03:34 PM
There is no need to dose calcium or alkalinity unless the alkalinity gets to low, and yours is fine (calcium will never get too low if alk is not declining). Magnesium seems fine.

I wouldn't bother with the Lugols dosing, but if you want to keep it up it is not likely hurting anything. Many of us who dosed iodine for years and stopped cold turkey saw no undesirable changes.

These have more:

The “How To” Guide to Reef Aquarium Chemistry for Beginners, Part 1: The Salt Water Itself

The “How To” Guide to Reef Aquarium Chemistry for Beginners, Part 2: What Chemicals Must be Supplemented

The "How To" Guide to Reef Aquarium Chemistry for Beginners, Part 3: pH

The “How To” Guide to Reef Aquarium Chemistry for Beginners,
Part 4: What Chemicals May Detrimentally Accumulate

12/22/2011, 06:04 PM
Thanks guys.

Randy Holmes-Farley
12/23/2011, 05:12 AM