Dosing Sugar (Sucrose) vs Glucose (Dextrose)?

[scribble]

The Fauna Marin product UntraMin-S lists glucose monohydrate as its primary ingredient (after water). And I was reading in another thread where someone said that the glucose in UltraMin-S is for feeding coral whereas sugar (sucrose) will feed the bacteria as in normal carbon dosing. Does anyone know anything about this?

I have had troubles with my acroporas being very light in color and a guy at a LFS recommended trying UltraMin-S because he thought my nutrients were too low. My acros have brightened up quite a bit over the last few weeks of using it. So I’m wondering… am I feeding my corals glucose or carbon dosing the whole system.

[Genetics]

I know a bit about the two and their differences.

Glucose can be used as a signaling molecule between zooxanthellae. By adding glucose to your tank you can actually keep zooxanthellae populations from becoming dense in corals (simplified: the coral isn't brown). Glucose is also an essential building block for growth. So, theoretically glucose additions may improve colors and growth in corals. In addition, it would also be used as a food source by bacteria.

Sucrose as a disaccharide does not have the same ability to limit zooxanthellae populations. From what I've found in the scientific literature it seems that high levels of sucrose cause issues with sps that appear as white band disease (theoretically high glucose levels could cause similar issues). Also, sps react by turning a deeper brown coloration which most in this hobby dislike.

For those running VSV I recommend using glucose, commonly sold as dextrose. For simplification this is what I recommend for dosing;

135g glucose (~6 tablespoons)
900mL 40% vodka
100mL White Vinegar

[Genetics]

Originally posted by scribble
My acros have brightened up quite a bit over the last few weeks of using it. So I'm wondering, am I feeding my corals glucose or carbon dosing the whole system.

Sorry missed this. You are definitely carbon dosing and highly likely that you are providing signaling for your corals that they have enough food to cause growth.

[scribble]

Wow! Genetics, thanks for the very informative reply. It makes more sense to me now. My acros were looking a little starved and pale and the UltraMin-S has helped them out a fair bit. From the ingredient list it looks kind of like Seachem Reef Plus, except for the glucose. I don’t want to actually dose enough glucose to be much of a carbon source though. I’m currently only doing 3ml per day of the UltraMin-S in a 300gal system with a lot of SPS. I can’t imagine that can be very much glucose, but none the less my acros seem to really like it (brighter colors and better polyp extension, generally looking happier).

I looked at buying glucose and you can get a 2 pound bag on-line for about 3 bucks (NOW Dextrose Granules, they claim it’s completely pure). I’m thinking about trying to dose it alone and see how it works out, UltraMin-S is quite expensive and a little hard to get. Fauna Marin warns about overdosing UltraMin-S causing green slimy algae outbreaks, I’m guessing if I overdose straight glucose something similar will happen I’m hoping I can dose just enough to help out my acros and not cause much nutrient reduction through being a carbon source.

[Genetics]

Why are you worried about a nutrient reduction? It will happen to differing extents based on how much you are adding. If you are trying to keep it from a level that will not cause reduction you should look at adding no more than 0.10ppm (that works out to be milligrams in your tank).

Also, UltraMin-S probably contains supplemental metal ions. These metals have been found to bring out colors as well. But I am uncertain how they actually do so.

[scribble]

The reason I don’t want to do much nutrient reduction is just because I’m assuming that the reason my acros have had such light colors and limited growth is that the nutrients are too low. I’ve tried some other supplements (amino acids, trace, etc..) and nothing has really helped so far. I’ve tried a lot of different things and nothing has helped much. The UltraMin-S has helped and I’m trying to figure out why. I have another aquarium in my living room that’s been running for about 6 years and is doing great, lots of acros, great growth and color. But in this newer system I set up in a spare room, the SPS just look like they are starving or something. The water parameters test out right where I want them, I do about 10% water changes every week or two, I have quite good lighting, etc… I’ve been assuming the problem is low nutrients, but I’m not sure. The only things that have seemed to help are not running my skimmer very much, adding more fish, backing off the lights, and now the UltraMin-S has made the biggest difference. Any ideas what may be going on?

You may be right about the metal ions helping as well. I’m going to order up some straight glucose and test it out, see if I get similar results.

[scribble]

A bit of weird history about this tank: I live in Houston and I got hammered by hurricane Ike last summer. I had no power for 4 days and the tank in my living room did ok but this tank went completely south, the water turned milky white and smelled horrible. Almost every thing died. When the power came back on I didn’t even want to look at it, I just let it go. After about a week it all cleared up and what corals survived looked great, much better than when I was diligently maintaining the system. But, after a few months everything when back to the old pale, starved-out look. It probably doesn’t look as bad as I’m describing, I just haven’t been able to even come close to the success I have had with my other reef tank in my living room and I’m still trying to figure out why. I thought about pouring a bucket of rotten fish in the tank every month or two to try and get that post-disaster look back.

[Genetics]

Scribble, do you feed meaty foods? You may want to look into that as that can drastically help sps health.

[Ellery]

Originally Posted by Genetics

I know a bit about the two and their differences.

Glucose can be used as a signaling molecule between zooxanthellae. By adding glucose to your tank you can actually keep zooxanthellae populations from becoming dense in corals (simplified: the coral isn't brown). Glucose is also an essential building block for growth. So, theoretically glucose additions may improve colors and growth in corals. In addition, it would also be used as a food source by bacteria.

Sucrose as a disaccharide does not have the same ability to limit zooxanthellae populations. From what I've found in the scientific literature it seems that high levels of sucrose cause issues with sps that appear as white band disease (theoretically high glucose levels could cause similar issues). Also, sps react by turning a deeper brown coloration which most in this hobby dislike.

For those running VSV I recommend using glucose, commonly sold as dextrose. For simplification this is what I recommend for dosing;

135g glucose (~6 tablespoons)
900mL 40% vodka
100mL White Vinegar

Hi Nate,

Not sure if you're still active but I was wondering about your dosing recommendation above. Is that the solution mix and how much per gallon are you suggesting?

I've been reading about another Taiwanese hobbyist that had great results dosing WHole Milk and Honey to his SPS tank and that looked phenomenal.

[Genetics]

Ellery,

This thread is an old one. At the time I was creating a mixture and dosing according to my tank needs. I never found a one-size-fits-all dose. I’ve followed some of the additives that have come on the market and find people have had varying success. I have no opinion on honey or milk as an additive as I have not come across aquariums using such regimens.