Skimmer Foaming Over

[ReefPony]

Hey, everyone. Got a bit of a question.

Have had a Reef Octopus BH100 HOB skimmer on my tank for the past few months. I've also been dosing vodka to help bring down nitrates in my tank since they were ridiculously high.

I got up to the dose that started bringing down my nitrate levels about a week ago but over the past couple of days my skimmer has been going absolutely nuts.

I've had to raise the skimmer cup almost to the highest level and there's still so much foam being created that it's coming out the airholes on the top and getting into side chambers where the water goes back into the tank.

Is this normal when vodka dosing or is my skimmer just a little out of control?

 

[jrozzi]

I had that same problem when I added a phosphate reducing media filter thingy. I took out the media and the foam stopped.

 

[whosurcaddie]

Its gonna need time to adjust. I would back down a few milliliters on the vodka and over time the skimmer will correct itself. Mine did the same thing except I have an in sump skimmer but the first month I started dosing it went haywire and now its performing better than ever thick black nasty stuff 24/7. One thing I would recommend is to empty the skimmer cup as often as you can even though its bubbling over that collection still has organics you need to remove.

Another note when you are removing that much tank water you are slowly lowering your salinity as well so keep an eye on that and top up with saltwater when needed.

Oh also feel free to switch to vinegar if you want its cheaper and serves the same purpose. 5% acetate white vinegar is what you want its what I carbon dose with.

 

[ReefPony]

I had that same problem when I added a phosphate reducing media filter thingy. I took out the media and the foam stopped.

Hmm... The only filter media I'm running now is a small bag of Purigen and an activated carbon filter sponge in a HOB filter.

Previously, I had most of that filter filled with Matrix media that I decided was probably causing more problems than it was solving since it seemed to trap a lot of stuff between the pieces that just broke down in there or got loose in the tank whenever I cleaned out the filter chamber.

 

[tmz]

Vinegar is fine to use if you dose it slowly but it's not any cheaper than vodka .
You need to use 8 times as much. I pay $ 14 for 1.75 liters of Bartons 80 proof/40% ethanol vodka vs $3.60 for 1 gallon of store brand vinegar (5% acetic acid). It takes about 4 gallons(3.7) of vinegar to equal 1.75 liters of vodka .

How much are you dosing for what water volume ? Heavy bacterial growth could;db be the issue.

 

[shesacharmer]

My skimmer went nuts this week and dumped 3 gallons of freshwater into my DT via ATO. Lucky for me my hob skimmer hangs over a bucket or that 3 gallons of skimmate would have been on my carpet! No matter how I adjusted the skimmer knob the flow would NOT reduce but I did discover that by tilting the skimmer just a bit so it was not sitting level I could adjust the bubble level. I have no idea why that worked but it's keeping me skimming.

 

[ReefPony]

My skimmer went nuts this week and dumped 3 gallons of freshwater into my DT via ATO. Lucky for me my hob skimmer hangs over a bucket or that 3 gallons of skimmate would have been on my carpet! No matter how I adjusted the skimmer knob the flow would NOT reduce but I did discover that by tilting the skimmer just a bit so it was not sitting level I could adjust the bubble level. I have no idea why that worked but it's keeping me skimming.

Fortunately, my isn't pulling out that much actual water. I've been using a spoon to scoop the foam out of the 2nd chamber of my skimmer and, over the course of the day, it's only about 25% of a typical 16oz plastic cup once the foam all breaks and releases the water.

The problem I'm having is the sheer amount of foam. Unfortunately, this particular model skimmer doesn't allow me to adjust the airflow into the pump so it's more or less "on" or "off". While I'm sure it has something to do with the vodka dosing, I'm not sure how to adjust my skimmer to reduce the sheer volume of foam it's producing.

 

[ReefPony]

Well, the problem seems to be subsiding a bit since I did my water change this afternoon. I think the water change helped (even though it ticked off my clowns since I really stirred up a storm in the tank before I started up the siphon) but I think the biggest thing is that I've cut my vodka dose back by 1ml.

Still a lot of foam in the skimmer cup but it's not (knock on wood) foaming over like it was previously.

My biggest concern is that it was the larger vodka dose that started bringing down my nitrate levels. Will the lower dose still be effective now that there is at least some population of anaerobic bacteria in the tank (I think its anaerobic bacteria that consume nitrates... correct me if I'm wrong)?

 

[tmz]

The bacteria are facultative heterotrphs. They assimilate some nitrogen , phosphate,and other things for their biological mass and use the organic carbon from the vodka or vinegar for energy. They can't make their own organic carbon like autotrophic organisms can.
Since they are facultative ,they use oxygen in aerobic activity and when it's exhausted nitrate is further reduced beyond the nitrogen assimilated by anaerobic activity as they use the oxygen from the NO3 leaving N which binds with N and forms N2 nitrogen gas which bubbles out of the tank.

This thread of mine regarding organic carbon dosing may be of interest:

http://www.reefcentral.com/forums/showthread.php?t=2134105&highlight=organic+carbon+dosing