Manual Dosing 28 Gal. Nano

[Luvthekeys]

I have a 28 Gal. Nano tank which is about two and a half months old. It was started with 15 lbs of live rock and 20 lbs of dry rock. My question relates to dosing the tank to keep up the levels necessary for a Reef Tank. I should mention I am new to marine tanks.

I have been checking all my levels almost every day trying to get a handle on what amount of dosing I should do. I should mention the tank has a good amount of calciferous macroalgae. I will post a photo so you can see the red and green types of macro algae.

I am dosing 15 ML of Kent Magnesium Tech M almost daily and can barely keep its level at 1350.

I am dosing baked baking soda and baking soda mixed with distilled water almost every day to barely maintain 8 to 9 dKH. I do not dose a lot for fear of shocking my tank inhabitants.

I am daily dosing 2.5 ML of Kent Liquid Calcium just to maintain 340 to 360 PPM

I also dose 1.5 ML of Iodine and Strontium and Molybdenum weekly.

There also is a large clean up crew consisting of hermits, snails, shrimp, three emerald crabs and a sand sifting conch.

Other levels, Nitrates between 5 and 10PPM. Ammonia less then .025PPM. PH is 8.2

There are four fish, Royal Gamma, Green Clown Gobie, Blue fin Damsel and a blue eyed golden midas blenny.

I also have some small corals the largest a Gonipora Flowpot Coral.

My questions are as follows:

Is this normal for a two and half month old tank?

Can I dose more to get my levels higher since this is a reef tank?

Could the calciferous Macro Algae be using that much of items I am dosing?

Is there something else I should be doing with these numbers?

 

[Randy Holmes-Farley Verified Community Expert]

Your tank cannot be using the magnesium in 15 mL of Kent Tech M every day (~10 ppm). Maybe in a week, with a lot of coralline growth, but that doesn't even look to be the case. But if you are using it to offset lower magnesium in water changes, that might be needed.

Maintaining 8-9 dKH for alkalinity is perfect.

The calcium is low, and may be low due to being lower salinity and/or using a low calcium salt mix.

What salt mix and what salinity?

IMO, you'd be a lot better of switching to a commercial or DIY two part, and then you can mostly not bother measuring magnesium and only measure calcium once in a while, basing the dosing of it on the alkalinity.

I don't think that dosing the iodine is helpful. I stopped dosing it a decade ago and never say any difference. Many have that same experience. Same for strontium. I'd stop both.

Do you have any calcifying macroalgae (halimeda species, usually)? The macroalgae I see mostly is not using any significant calcium or alkalinity.

 

[Luvthekeys]

Thank you for the reply. In answer to your question my salt mix is Instant Ocean Reef Crystals. I should have noted my salinity earlier. It is 1.025 holding steady.

I will take your advice and stop dosing Iodine and the other element.

I was told most of my red algae is calciferous macro Algae. Yes I do have Halimeda but it does not do very well in my tank. Most of the live rock was from Tampa Bay. There is a yellowish brown kelp looking macro algae to the left middle of the photo that I am not sure what it is.

I should also note for a few weeks I could not get my Alkalinity to go above seven and it even dropped to six. I was dosing with Kent PH Buffer. When I switched to a mixture baked baking soda and baking soda it seemed to correct the problem.

At this point i do not mind manual dosing for a tank this small. I am basically housebound due to cancer so it gives me something to do.

My main concern is the well being of all the inhabitants including the corals.

Can I raise the amount of liquid calcium to get the levels up to around 400?

It is interesting that you say my tank can not be using that much Magnesium, not that I am disputing your observation. I am using the Seifert Test kit for Magnesium and can see the numbers fall almost daily. I am at a loss in this instance. At one point I had it at 1410 and within three days it dropped to 1320. Maybe it is me doing something wrong when I test.

However on the bright side everything looks good and all inhabitants appear healthy.

 

[Randy Holmes-Farley Verified Community Expert]

I suspect your calcium kit may not be working well (or your salinity measuring device is reading higher than reality). RC at a sg of 1.025 should have calcium above 400 ppm. I'd suggest trying it on some new salt water.

You'll find that calcium and magnesium will rise about 6% by boosting the salinity to 35 ppt (sg = 1.0264), which is a typical ocean average. Magnesium will rise from 1300 ppm to 1373 ppm, and ion any case, I suggest that 1250-1350 ppm is a good target range. There's no need to go above 1350 ppm.

Do you know the species of red algae that you have? Is so, we can determine if they are calciferous. Most are not.

 

[Randy Holmes-Farley Verified Community Expert]

It is interesting that you say my tank can not be using that much Magnesium, not that I am disputing your observation. I am using the Seifert Test kit for Magnesium and can see the numbers fall almost daily. I am at a loss in this instance. At one point I had it at 1410 and within three days it dropped to 1320. Maybe it is me doing something wrong when I test.
.

The only way that magnesium is appreciably consumed in a tank like yours is by incorporation itno calcium carbonate. In that situation, the relative consumption rates are about:

2.8 dKH of alkalinity (1 meq/L)
18-20 ppm calcium
0.1 - 2 ppm magnesium

So to use 1o ppm of magnesium, you need to be consuming impossibly huge amounts of alkalinity (>= 14 dKH) and calcium (>= 100 ppm) each day.

I discuss magnesium in several articles, but this is probably the place to start if you want to read more:

http://www.advancedaquarist.com/2003/10/chemistry

 

[Randy Holmes-Farley Verified Community Expert]

However on the bright side everything looks good and all inhabitants appear healthy.

That's the importnat thing.

If you want to keep dosing the iodine and strontium "just in case', it is fine to do so.

Then some time later when the tank is more established, you can stop one or both and look for changes yourself.

This has more on iodine:

http://www.advancedaquarist.com/issues/mar2003/chem.htm

and

http://www.advancedaquarist.com/issues/april2003/chem.htm

and this on strontium:

http://www.advancedaquarist.com/issues/nov2003/chem.htm

 

[Randy Holmes-Farley Verified Community Expert]

In terms of calcium and alkalinity dosing, this has the pros and cons of most methods:

https://www.reef2reef.com/blog/the-many-methods-for-supplementing-calcium-and-alkalinity

 

[Luvthekeys]

Thanks again for your reply. I am using an API test kit for Calcium. I had bought a Hanna test kit for Calcium but it did not work properly and I returned it. I will double check the calibration of my refractometer today. It is all right to use distilled water am I correct.

I went back and checked the red macro algae is Red Graciela. My mistake I was not told it was calciferous. the three other species of Red Algae i have I do not know. The two near the top, one looks like little trees and the other has branches of fairly large bubbles on them. Do you have any idea what the yellow macro algae on the left side of the tank is? I would love to know Tampa Bay surprised me with. None of the algae was on the live rock when i put it in the tank. It only had Halimeda. I now have two sea urchins that are growing like crazy and some other beneficial hitchhikers.

I hope you are right and it is my refractometer that is off. Just went and calibrated my refractometer and it was on zero. I even took it out of calibration and calibrated it. I also have a hydrometer which I sometime check to see it the two agree.

 

[Randy Holmes-Farley Verified Community Expert]

Thanks again for your reply. I am using an API test kit for Calcium. I had bought a Hanna test kit for Calcium but it did not work properly and I returned it. I will double check the calibration of my refractometer today. It is all right to use distilled water am I correct.

Depends on the type of refractometer. Unless it claims to be a "true" seawater refractometer, it is almost certainly a brine refractometer and will have some inherent error if calibrated with RO/DI and then used for seawater. Not enough to explain your low calcium, but enough to want to use a 35 ppt standard.

I'm not sure what the yellow one is, but it does not look like a calcerous seaweed. Such seaweeds are fairly uncommon and are quite stiff due to the internal calcium carbonate. Anything that flexes easily is just a "regular" seaweed.

 

[Luvthekeys]

If there is a true problem would I get any participation of the calcium in the water column? I do a water change on Sundays so I will do a complete check of the new salt water. I know hydrometers are notorious for being off, but if the refractometer and the hydrometer agree would that not confirm the salinity? Maybe I am putting too much emphasis on testing. I mean doing almost every day is a pain but with a small tank I do not want it getting out of control.

 

[Randy Holmes-Farley Verified Community Expert]

I'm not sure what you mean by getting precipitation due to a "true' problem. The only time folks see calcium carbonate precipitation in the water column is from immediate and big overdoses of high pH additives, such as limewater (kalwkasser) or an alkalinity additive. In those cases, the tank can look like milk (mine has ).

Having two devices agree is good, but not foolproof by any means.