Question regarding Tunze 9019

[king1522]

I intend on placing the skimmer in my sump. The instructions state "the Comline DOC skimmer has to be placed in a zone with quiet water. The proximity of a drain outlet may disturb the formation of foam". I want to place it in the same chamber as the drain from the tank. Has anyone had a problem with this or do you have an opinion?
Thanks

 

[pjf]

Turbulent Sump and Finicky Skimming

Turbulent Sump and Finicky Skimming

I have a Tunze 9010 in a very turbulent sump with 900 gph flowing through it. To check the salt spray, I have a custom acrylic cover over the top of the sump with cut-outs for the skimmer and the overflow drain. I can see turbulence causing the sump water level and the foam in the reaction tube to rise and fall.

I have no problems with foam production as I can fill the stock 9010 collection cup within minutes with the air adjustment valve opened fully. The skim collection can vary from 200ml to 400ml of wet skim daily. On occasion, the collection cup may fill to the brim (700ml) overnight.

I do have an issue when using my new foam extraction unit. It has an almost airtight fit with the skimmer body which results in greater air flow. I find it to be "sensitive" as the difference between no skim and a flooded collection jar is less than a quarter turn of the air valve. The foam production varies with feeding and salinity. Adding a cup of salt can cause the skimmer to go from no foam to a flooded collection jar overnight.

I am told that a less turbulent sump will produce foam with more consistency and less sensitivity to changes in water chemistry.

I plan to replace my return pump with a smaller pump and add in-aquarium powerheads. Perhaps that will result in a less turbulent sump and less variation in foam production.

 

[kodyboy]

I have mine in a turbulent sump too, no problems here

 

[king1522]

'foam extraction unit", what's that??

 

[kodyboy]

a different kind of collection cup

 

[pjf]

A picture of the foam extraction unit is in the middle of this webpage: http://tunze.com/149.html?&L=1&C=US&user_tunzeprod_pi1[predid]=-infoxunter028.

It fits on the skimmer more tightly than the regular collection cup. The more air-tight fitting results in more powerful skimming. I think that I am close to dialing in the correct air valve setting but it has not been easy.

Kodyboy is correct to be skeptical that the sensitivity is the result of a turbulent sump. Many factors could be involved. While cleaning the skimmer, I noticed some salt creep in the air path under the rim of the skimmer.

 

[pezcubano]

How much $$$ is a foam extraction unit? Would you be happy with the Tunze w/o the foam extraction cup? Is it worth it to you?

 

[pjf]

Dialing-In Blues

Dialing-In Blues

Per this webpage (half-way down), the foam extraction unit is $95.28: http://tunze.com/149.html?&L=1&C=US&user_tunzeprod_pi1[predid]=-infoxunter028.

I bought the unit for vacations but it is fine for normal use. By using a collection jar (cut a 2" opening in a plastic soda bottle), one needs not empty it every day. The collection stops if the collection tube is under a couple inches of skim. You need to cut the tube to the correct length for your collection jar.

Tunze recommends the foam extraction unit to maximize skimming. It has a collar and fits more tightly which results in more air directed into the reaction tube instead of escaping around the edge of the tube.

A quarter turn of the air valve can be the difference between no skim and a flooded collection jar. It can go for hours with no skim and then suddenly flood the jar. I think I've got it to collect an average of a cup a day but I'll have to wait another few days to make sure that I have the right setting. Once I do, I'm going to glue the air setting in place.

You may want others with the foam extraction unit to chime in. My water chemistry is out of control because I installed a carbon and phosphate removal reactor at the same time. My installation of new gear is not being well controlled.

 

[pezcubano]

Thanks!!!
I'm probably going to get a similar situation on my hands, cause I'm installing different components this week.
I'll work on a collection jar once I get the skimmer.
Thanks so much...

 

[sjm817]

Re: Dialing-In Blues

Re: Dialing-In Blues

<a href=showthread.php?s=&postid=10024975#post10024975 target=_blank>Originally posted</a> by pjf


You may want others with the foam extraction unit to chime in. My water chemistry is out of control because I installed a carbon and phosphate removal reactor at the same time. My installation of new gear is not being well controlled.

One thing about carbon in particular is it "competes" with a skimmer removing DOCs. I run a canister filer full of a lot of carbon. I use it on a timer because it holds so much. When I change the carbon, skimming production decreases. I'm still trying to figure out the right balance of the two. I want the skimmer doing the heavy lifting and the carbon just to supplement.

GFO will initially cause a drop in Alk which should return to normal after a couple days.

 

[pjf]

Thanks for the explanation, sjm817. I know there is an interaction between the skimmer and the GAC/GFO reactor but I couldn't figure out the nature of the interaction.

I'm curious as to when you have your timed carbon reactor running and why. I have two timers with extra outlets. One is for the day lighting and the other is for the RDP refugium lighting. I can plug my reactor into either outlet for either day or night use.

 

[sjm817]

IMO, a canister filter is a very good way to run carbon. I had a Fluval 404 kicking around from my old FW setup, so I figured I might as well put it to good use. It is a large unit and holds an entire 3.65L container of Black Diamond. My system volume is ~ 250G, so that is ~ 1 tbsp/gal if my math is right. I dont really want the carbon doing the skimmers job (the competing thing), so I thought cutting back via a timer would be a way to do that. I run it on a 1 hr on / 5hr off schedule, so it runs 4hr/day. I dont really know if this is the best way to do this, but it seems OK. If I were to pick day or night, I would run during the night when feeding is not happening.