Vinegar, Phosphates and Algae Reduction

[CastAway]

Randy, the latest parameters for my 210g total system volume were:
She -1.025
dKH - 9.0
Ca - 445
Mg - 1300
pH - 8.0
PO4 - 0.04
NO3 - <0.25

I skim, run GFO and have a 25g refugium full of macro which I harvest regularly. I probably feed too heavily, and have about a dozen fish.

I struggle with algae lately and am curios about manually dosing vinegar.

What would be a reasonable daily dose to start, and how long might I wait to see results before adjusting? What effect might I see on my parameters, if any?

 

[Randy Holmes-Farley Verified Community Expert]

It might help, but in my system, when I was uppping and upping the dose of vinegar, I never was able to reduce certain algae (specifically, Caulerpa racemosa) despite really larger doses (410 mL per day to my 120 gal display with about 250-300 gallons total water), so much so that the water became cloudy with bacteria. My guess is that the Caulerpa was as competitive for nutrients as were the bacteria consuming the vinegar. Normal green hair algae may be a lot less competitive.

So it is a fine experiment, but I would not be assured of success.

I'd start at 10 ml per day of normal distilled white vinegar (5% acidity) in the mid AM (if you can) or 5 in the AM and 5 in the mid to late afternoon, and ramp up 10 mL per week for a number of weeks and see how it goes.

Remember it reduces pH when added, so add away from creatures and when pH is high. The more spread out it is, the better.

 

[CastAway]

Thanks Randy!
This is the algae I'm battling; green slime perhaps...

 

[Randy Holmes-Farley Verified Community Expert]

I can't tell if that is cyano or green hair algae, but if it is cyano and if it starts to get worse on vinegar dosing (meaning it is a species that can metabolize the vinegar), I'd suggest stopping the vinegar.

 

[CastAway]

We'll see Randy. Should be obvious. Historically cyano in my system has been the conventional maroon. Could be cyano though - always a ton of bubbles under it. Blows off my rock with a turkey baster, but not so easily removable from the gravel.

Thanks again!

 

[Randy Holmes-Farley Verified Community Expert]

You're welcome.

Good luck!

 

[Harold Green]

From the picture it looks like the majority of the growth is on the gravel. Has the gravel bed been left unstirred for a long period of time where detritus may have built up? Are your mp40's flowing across the sand bed?

 

[CastAway]

I wish in hindsight that I'd have bought MP60's! No, they are positioned about 10" below the water line.

The sand bed is 1/2 to 3/4" thick, and I do not stir or vacuum it. I have been turning it over, burying patch of the algae/cyano, but it surfaces in time, kind of like cyano will.

I have a water change pending and will vacuum it. Perhaps I should wait a bit after that to try dosing vinegar.......

 

[Harold Green]

Let us know if it works.

 

[CastAway]

Four days into the vinegar, dosing 5ml twice daily, my goni closed up tight. Stopping the vinegar now just in case. Water change today and vacuuming the gravel. Ugh.

 

[Randy Holmes-Farley Verified Community Expert]

Stopping sees prudent. I've not seen this reported before.

 

[CastAway]

Stopped the vinegar. Vacuumed the gravel. Moved a nearby chalice on the chance the Goni was getting stung.

Algae/cyano now returning. Thinking about vodka.

If 2-5ml doses was a good start with vinegar, and vodka is 8x more powerful, is 2-1ml doses a good start?

 

[Randy Holmes-Farley Verified Community Expert]

Yes, that's reasonable.

GFO would be another option, as would growing macroalgae.

 

[CastAway]

Thanks Randy. I can't tell you how awesome it is having you here.

I run GFO, about 10-12 Tlbs of Foster & Smith PhosPure in the 210g system. However, I'm sure I don't change it out near enough. Once every three months, maybe.

I also have a refugium, about 25g in volume, with about three types of macro; a couple of slow growing red ornamentals and a fast growing c. Brachypus, which I harvest heavily about every three months, maybe more. There is a 5-6" sand bed in the fuge, but I'm concerned the matting caulerpa inhibits advection through the bed.

See anything wrong?

 

[Randy Holmes-Farley Verified Community Expert]

Thanks!

Nothing seems wrong except letting the GFO go for 3 months.

 

[CastAway]

Although I have a tendency to "speak too soon" when it comes to identifying issues and resolutions in my system, but I think I am seeing a reduction in this green cyano finally.

I am manually dosing vodka twice a day, 2ml in the am and 2ml in the evening - about 7 days now. I think I'm seeing an increase in skimmate, and I am definitely smelling an increase something! When I dumped my skimmate overflow today, WOW! It was different.

 

[nebraska dreamin]

This has me stumped as well....

no3 0 po4 0

have the same green slime with a dash of some brown hairy cyano ish looking stuff. i had dosed dr tims for a bacteria source and ive heard that that or vinegar can cause that brown hairy cyano looking stuff.

 

[nebraska dreamin]

is it possible we have too much of a bacterial population??

 

[CastAway]

At one point early in my system, my gravel started to clump and solidify. I wonder if, in my own system, PO4 was somehow binding with my sand and rock, and isn't now providing a food source for algae and cyano, all the while measurable values are low.

Always been confused about that. I mean if my macro algae are growing gang busters, and yet I don't measure high NO3 and/or PO4, I still know they're there, right?

 

[CastAway]

Just for a frame of reference, here is that same corner of my tank now, after one vacuuming and a week of vodka.