Vitamin C (carbon source) dosing, no skimmer. It CAN be done. Carefully.

I just wanted to share with everyone something that I'm trying on my 11g nano, since I am convinced that this can work, and I'm only risking a small tank if something does go wrong. But, if it works (which it seems to), it can be a huge benefit to those with tanks struggling with high nitrates and slack coral growth. With, or without, a skimmer. If you have no skimmer, read my dosing level carefully, and do not exceed it, and only try this with buffered vitamin C powder.

As for it's actual usefulness, you may decide however you want, but I've used this in the past and can vouch for it's usefulness, particularly to soft corals (zoa/palys in particular), for LPS, and possibly for SPS.


First, this is dosing a very concentrated source of ascorbate, using 100% Sodium ascorbate (aside from a trace of buffer they add to it, which adds a touch of alkalinity to our tanks, in a very useful amount). You can get it at places like iHerb.com

Now, here are the specs, the hypothesis, and the 10-day results. Keep in mind that the hypothesis is based on my experiences from 6-8 months of dosing VC powder on my 80g system a few years ago, but it had a big skimmer on it. So I expect slightly different results (ie, no phosphate removal).


Specs-- tank has been set up since early October 2011-- an 11g rimless from Green Leaf. 36X9X9, approx. Nitrates were at about 15ppm, but (oddly) the phosphates showed a 0.00ppm on a Seachem kit 10 days ago. Dosage-- 1/8th teaspoon per each (approx) 10g of water.


Hypothesis--- First, some unusual benefit to soft coral and LPS growth. I've seen with my own eyes in my old system, 6-8 months worth of very good growth and overall improved health for zoanthids, softies, and LPS, but it's very hard to quantify, you just have to experience it yourself. I wanted to reproduce this in my current nano tank. I have absolutely no idea what benefit Vitamin C has for soft corals unless they are feeding on the bacterial blooms that happen.

-----------Second--- I wanted to reduce the nitrates, and since the bacteria that reduce nitrates will just convert the nitrate into nitrogen gas, a skimmer is not needed to remove the bacterial film. Phosphate, on the other hand, would NOT be removed. It would just return to the water column when the bacterial bloom died off, or it will be incorporated into the soft corals as they grow (and be replaced by the daily fish feedings, hopefully holding steady).


10-day results, which are insufficient to make any sort of dogmatic claim. However, the ONLY thing that's happened are the things I just listed above. The softies are polyped out more (particularly, a couple zoanthid colonies that had been closed up for some reason, and my Tyree green leather which has always been a grouchy drama queen--- now it's open every day). Again, I have absolutely no idea (other than possible bacterial feedings) why soft corals respond to Vitamin C dosing like this.


Also, nitrates have dropped from 15ppm down to 2ppm in 10 days. This is with dosing 1/8th teaspoon (using an actual 1/8th tsp scoop), every day, in the mornings.


My alkalinity is holding (seemingly) steady at 10. According to several tests that I've done using various amounts of RO water and VC powder, 1/8th tsp of this brand VC powder raises 10g of water by 0.1dKH. 10 days is insufficient to say "exactly my alk consumption" since 10 days is only 1dKH.

At the very least, it's not raising my alk in a way that would alarm me, hopefully my few stony corals and corralline algae will increase enough such that high alk is never an issue.


Finally--- I have not had a single sign of oxygen deprivation in the tank. The bacterial blooms from that small dose of Vitamin C has not clouded my water at all, nor are there any slime-snot strands in my tank like you see when carbon sources are overdosed sometimes.

 

A question please?

Is there a skimmer connected to the 11 gallon?

Well dang it I did not see the entire title, hmmm no skimmer very very interesting.

 

None.

Which I am aware of the risk--- but as you can read in the post, I've not had any serious bacterial bloom that would cause oxygen depletion. Not at the small doses I'm dosing.


BTW, it's a myth that carbon source dosing requires a skimmer to remove nitrates. All carbon source dosing seems to do is accelerate the activity of common denitrifying bacteria, which convert the nitrate into harmless nitrogen gas. There are risks to this---- I know for a fact that dosing sucrose into a system with nitrates, and NO water flow (ie, a big trash can full of high-nitrate tank water)--- you end up with a horrendous hydrogen sulfide bomb. I tried this once, years ago, and it worked wonderfully. One big dose of sucrose (a couple tsp if I recall correctly) reduced the nitrates from like 20-30ppm down to around 5ppm in a couple days, but there was no water flow and the whole can of water smelled like Godzilla farted, so I just dumped it out. I've never smelled the hydrogen sulfide when dosing Vit C, but who's to say it couldn't happen if I overdosed.


However, without a skimmer, no phosphate is likely to be removed, since it isn't as easily converted into a gas like nitrogen. My guess (which is all I can make) is that phosphorus is used up some by bacteria, and then returned to the water if/when the bacteria dies. Or, perhaps, is consumed by the food cycle in the tank.

 

I appreciate that response and it makes a lot of sense.

I imagine with continued use the nutrifying and other beneficial bacteria will develop a larger population and will discontinuing the Vit C use abruptly cause an issue?

Carbon dosing without a skimmer has always intrigued me, probably because I do not run a skimmer but the risk always scared me.

 

Lol, dosing without a skimmer should scare you . However, the last time I used Vitamin C powder, I was shoveling nearly 2 full tsp per day into an 80g system and never had any sort of bacterial bloom that fouled up anything, and got great results. That was my experiment to see "just how much, and how useful" it could be. I stopped at 2 tsp because I saw no increased benefit, and this stuff isn't cheap for large tanks. So I went back to 1 tsp per day (in half doses, twice daily).


If I were to stop dosing this 1/8th tsp in my 11g tank, I suspect nothing bad would happen immediately, but over a few weeks the nitrates would probably creep back up. Plus my alk would lower (from consumption by the flora/fauna) unless I used a different source of alk. I love the fact that this stuff is buffered, it really does pack a 1-2 punch.


I do not think the denitrifying bacterial colony in this tank is going to be so large that an immediate die-off of the bacteria would cause any problems. At least, I don't think. I hope not lol.

 

BTW this is the tank I'm talking about:
http://www.3reef.com/forums/show-of...leds-live-beer-bottle-129686.html#post1289061

 

12 days of dosing 1/8th tsp into about 10g of water, no skimmer. Results, still great. Water is extremely clear and the corals are extremely healthy looking, except for a small patch of "bam bam" orange zoas--- but they were acting up before the dosing started, and half of them are now open (where they weren't open much at all before the dosing).



One odd observation that maybe you guys can help me figure out. The water is so extremely clear and "particle-devoid" that I think it must have something to do with the carbon-source dosing. I have absolutely NO mechanical filtration on this tank.

This tank had, from the first couple weeks, always looked a bit "snowy" which was fine with me--- I knew I'd have particulate waste in the tank since there is no skimmer or mech filtration. But this is the clearest I've ever seen it.

Do you suppose the carbon source dosing is fueling the bacteria to consume particulate waste?? I really don't know.

 

I've heard that is a side effect fro vit c dosing. The other side effect is the nastiest smelling skimate of all time for the same reason, new hungry bacteria. I've read alot of posts of people dosing vit c for a few weeks every year just to eat up detritus that otherwise might be forgotten. Food for thought (forgive the pun)

 

Ok, glad to hear that.


On my last system, I had a pretty decent skimmer (an old Coralife 240 with a drastically upgraded pump and a beckett injector), and never noticed the change in skimmate. I always skimmed wet anyhow (as part of a "water change" scheme) so maybe that's why I never noticed a change in the smell.


I'm glad to hear that others have reported a change in water clarity. So far I've observed, from dosing one product:

--Improved coral health-- most corals are now less "fussy" about the tank and are open/polyped out. I am also seeing faster growth on several zoa colonies than I had before. NOTHING drastic though.

--Reduced nitrates. I'll test again this weekend to see where they went from 2ppm.

--Alkalinity dosed daily since there's a touch of alk in every dose in the buffered VC powder.

--Increased water clarity.



I'm only 12 days into this. It's way to early to say that this is a big deal or not, but it's looking good. I'll see what the long-term effects are in the coming month or three .

 

Tested nitrates, Day 13 of dosing 1/8th tsp in the 11g tank.

Nitrates have slightly dropped. They were at 2ppm, now they are around 1ppm but it's hard to say. It's definitely "lighter pink" on the Seachem kit, than it was on Day 10.


I'm starting to see something odd in my Xenia--- both the "white" pom-pom and the standard silver stuff---- the tentacles are all looking bleached. Kinda. Not quite stark white, but they both seem to have less pigment in them of some sort. They aren't acting up-- they are extended, and seem to be growing, they just look unusual now. Not a clue what's actually going on lol.