A few Tunze 9011 Problems

[Ycore]

I've been running my Tunze 9011 now for a few months, and have a few issues.. One I thought would go away on its own over time, the other simply relates to its performance.

1) Micro-Bubbles. I run it in sump with the standpipe and sponge and have serious micro-bubble problems even after a few months. This is with a baffle/bubble-trap in place. The bubbles are coming from the water surging out of the standpipe, whose volume is too great to be entirely absorbed by the sponge. I.e the majority of the water flows down the sides of the sponge rather than through the sponge itself. It seems based upon my forum searches on similar issues that the volume of water exiting the standpipe may be too great?

2) Skimmer performance: I have a well stocked 50G tank with 12G sump. I never seem to get a "solid" foam head. I basically get a foamy "ring" which is slowly "burped" up the neck until it overflows into the collection cup, and then the process repeats. I don't get a solid foam that fills the neck, constantly pushing tiny amounts into the collection cup as others describe. I get about 100ml of tea colored skimmate every three days, at which point unless I clean the collection cup output drastically decreases.. Both the type of foam head I get, the performance, and the frequent cleaning it needs (every 3 days/100ml of output) just doesn't seem right.

Maybe 1 and 2 are related? Any insight would be appreciated.

 

[Ram Jr]

I think your sump is too small. if the sump was longer the bubbles would be able to pop b4 it went to your display. I also think that this skimmer is way too big for such a small tank.

 

[yeldarbj]

for the bubbles: How much flow do you have going through your sump? If you have too much flow especially in that sized sump, the bubbles may be getting sucked through your baffles too quickly, without having a chance to settle to the top.

for the performance: It could be the size of the setup. I ran a 9010 skimmer in-tank on a 65g sumpless setup for a couple years. It was a fully stocked, loaded sps tank. I never did get much skimmate and the foam was frothy and not always consistent as you describe. But the tank itself thrived. I think a lot of it has to do with the skimmer being a bit oversized for the size of tank.

I had such good luck with that tank, that I recently took off my cone skimmer (that was probably skimming too much) on my new tank (about 100g net) and picked up a 9010 to see if I could repeat the results of my previous tank.

 

[Ycore]

The skimmer was actually recommended by Roger for this tank, as it was a better value than the model one size smaller. The 200+ gallon rating for the 9011 is for a FOWLR; for a fully stocked SPS tank the rating becomes a lot less, so though it is on the high end, I don't think it's too big for my tank per se.

I will admit that the low skimmate production may be a result of running a rather medium stocked low nutrient tank, plus I use a filter sock so the skimmer doesn't have much gunk to deal with.

I've come across a few posts of people using this skimmer with a similar sized sump (hell, one of the biggest reasons to go for a Tunze is because of it's small footprint), but don't deal with a micro-bubble problem. The flow through the sump isn't huge, but I feel the baffles don't deal with the problems not because of flow rate, but because the bubbles are so micro in size they almost have no buoyancy.

I really think the issue is the flow rate out of the standpipe-- after watching some youtube videos of the 9010, the flow rate is such that all water is absorbed through the sponge and cleansed of micro bubbles. In my case, the flow rate is greater and the majority of the water spills down the side of the sponge rather than going through it.. The question is, what controls this flow rate and how do I alter it?

 

[yeldarbj]

I think to some degree you answered your own question regarding performance - medium stocked, low nutrient tank that's on the smaller size of the rating scale for the skimmer.

What size return pump do you run? Is the water turbulent in the sump?

What is the depth of the skimmer? My standpipe is only a little more than an inch above the water line. Water is just gently flowing out. I don't even use the sponge. Do you get an even stream out the back hole? I almost have the opposite problem, I feel like the flow out of the standpipe is not enough. The new pump on the 9011 must be nice.

Have you tried adjusting the air input?

 

[Ycore]

Depth of the skimmer is about 5", but supposedly it doesn't matter when using the standpipe as long as it's at least 4" submerged.

I wouldn't say the water is turbulent per se, just a calm fast flow. I use the Tunze silence 1073.040 as my return pump.

Water definitely shoots out of the hole in the back. The flow out of the standpipe is definitely related to how well set the pipe is in its slot, as well as the fitting of the cover on the bottom side where the pipe fits. Both in my case were annoyingly loose and constantly falling off/out. Since this area is not needed in a servicing capacity, and I would always use the skimmer in sump, I glued the side cover in place to stop it from falling out. This certainly gave me the best flow out of the pipe, however I am unsure how the flow through the standpipe relates to skimmer performance. All I know is that my flow is so great it overtakes the sponges absorption capacity.

I think to some degree you answered your own question regarding performance - medium stocked, low nutrient tank that's on the smaller size of the rating scale for the skimmer.

What size return pump do you run? Is the water turbulent in the sump?

What is the depth of the skimmer? My standpipe is only a little more than an inch above the water line. Water is just gently flowing out. I don't even use the sponge. Do you get an even stream out the back hole? I almost have the opposite problem, I feel like the flow out of the standpipe is not enough. The new pump on the 9011 must be nice.

Have you tried adjusting the air input?

 

[rvitko]

You mention a high flow rate from the stand pipe, I think that is the key, something is wrong, the skimmer is not taking in enough air and so the water flow is much higher. Basically the pump is a roughly 500gph pump, that can be 350 of water and 150 of air or anything in between and so the less air the more water. The number one thing that cases what you describe is the sponge is above the top of the pipe which pushes water into the air intake and cuts air flow, or the pipe is not in the elbow all the way or the elbow is pushed in too far and damns up water into the air intake. It may also be the airline is pinched or kinked or not fully inserted into the venturi nozzle.

The skimmer is fine for your size tank, overkill, but it is what I would use if I wasn't using the 9002, I like the 9002 and 9011, these always perform well and are the best value from our line. There probably isn't a ton to remove but the root issue is this high water flow, water should barely bubble from the pipe.

 

[Ycore]

Yes, the flow out of the standpipe is very significant, definitely not a slow gurgle and more of a steady rapid stream that actually creates a waterfall sound as the water spills down the side of the sponge. The sponge is not set above the pipe, so that's not it.

I can't say for sure about the airline being crimped, however looking from above with the collector cup off, the plastic tube inside the skimmer doesn't looked crimped and is firmly attached to the inside of the air screw.

It sounds like it is most likely the dreaded standpipe being in too far, or not far enough. I use the term "dreaded" as both the standpipe and sliding door compartment snap in thingie were extremely ill fitting. The compartment snap in easily popped out of the skimmer chassis if you so much as looked at it wrong, and the standpipe had too much play in its socket. Any minor adjustment in my sump risked knocking one of these components out, and yay, I was yanking the skimmer out of the sump-- no minor endeavor in a tight space. I eventually had to glue the sliding door in, and put a small bead of glue around the seam of the standpipe to keep it in place..

Assuming I can remove the standpipe (I only used a bit of glue around the seam), how do you suggest I determine the proper position of the standpipe? With both "too far in" and "not far in enough" being the possible cause, and the entire range of play being maybe 1cm, I'm not sure how to properly gauge proper placement of the pipe..

edit: Forgot to mention.. I'm not sure whether this helps in a proper diagnosis, but adjusting the air screw has no effect on how much water (at least not with the naked eye) flows out of the standpipe.

You mention a high flow rate from the stand pipe, I think that is the key, something is wrong, the skimmer is not taking in enough air and so the water flow is much higher. Basically the pump is a roughly 500gph pump, that can be 350 of water and 150 of air or anything in between and so the less air the more water. The number one thing that cases what you describe is the sponge is above the top of the pipe which pushes water into the air intake and cuts air flow, or the pipe is not in the elbow all the way or the elbow is pushed in too far and damns up water into the air intake. It may also be the airline is pinched or kinked or not fully inserted into the venturi nozzle.

The skimmer is fine for your size tank, overkill, but it is what I would use if I wasn't using the 9002, I like the 9002 and 9011, these always perform well and are the best value from our line. There probably isn't a ton to remove but the root issue is this high water flow, water should barely bubble from the pipe.

 

[Ycore]

If it helps in troubleshotting , here's a link to a video of the standpipe output:

http://s374.photobucket.com/albums/oo187/jrothstein_photos/?action=view&current=IMG_0111.mp4

 

[rvitko]

That actually doesn't look bad, I was imagining a much more violent output which I have seen before. You are a day away from us by UPS and 2 days by mail, could you send the skimmer sans cup so I can check it out? I will be in Dallas for the DFWMAS fragswap in Feb, I could also look at it then if you could bring it and can get by. I am sure it is something really minor. My guess is the air hose inside the skimmer that attaches to the nozzle of the pump is pinched between the pump and body or is kinked, or the venturi nozzle is damaged in some way. What you show is too subtle to be anything with the pipe.

 

[Nautilus8]

Hi there. I am having exactly the same issue(s) that you had with your Tunze 9011 skimmer. Were you able to solve them?

 

[rvitko]

From my experience these issues have many possible culprits, a broken venturi, excess sediment, improper assembly, a kinked airline, very high flow past the skimmer reducing contact time or use of certain additives or media. The most common thing I find is a venturi nozzle that has a crack or some leakage reducing pressure and a lot of sediment in the skimmer and this combination will result in almost no production.

 

[Nautilus8]

Thanks for your reply. This is a Brand New skimmer, has been in use for less than a month. Sediment is not an issue, airline is fine.

My Main problem are the microbubbles... The skimmate looks ok to me.

With all due respect... "Broken venturi" "cracked venturi nozzle"... are you kidding me??? I paid over US$350.00 plus shipping for a deffective product? What kind of QA/QC does your company have? I this a common problem with your skimmers?!?!!!!

Nevermind. I would like to very respectfully request directions to a website/document that provides me with propper instructions on how to diagnose and repair "Broken venturi" "cracked venturi nozzle" issues. I have been working with and repairing scientific equipment for a couple of decades know, just give me some good troubleshooting literature and I will fix this....

By the way... Did Ycore ever get his skimmer working properly?

Thanks in advance for your attention to this request. Best rgards..

 

[rvitko]

Regarding the venturi, they break in shipping. They break because they are shipped from Germany to Texas, Texas to your dealer and your dealer to you and occasionally there is even a wholesaler in the middle, the defect is that the glue joint may not be perfect, this is not something that we can detect besides physical inspection and a QC note is in every box by the inspector, we do all we can, but if at any of these shipping legs it is treated roughly, it can break. It is not common, but we have had a large box of skimmers be dropped at some point and the box shows no physical damage and there is no way to detect this problem.

In the absence of a performance issue the microbubbles may be normal, the skimmer will emit some microbubbles, especially when used with the sump kit, all skimmers due. The original poster had performance issues and that was the main point of my post. Microbubbles are more of an issue with sump design and flow through the sump to avoid having them returned to the tank. I would need to know more about where the bubbles come from on the skimmer body and may be able to suggest a way to minimize them.

 

[Mindflux]

Thanks for your reply. This is a Brand New skimmer, has been in use for less than a month. Sediment is not an issue, airline is fine.

My Main problem are the microbubbles... The skimmate looks ok to me.

With all due respect... "Broken venturi" "cracked venturi nozzle"... are you kidding me??? I paid over US$350.00 plus shipping for a deffective product? What kind of QA/QC does your company have? I this a common problem with your skimmers?!?!!!!

Nevermind. I would like to very respectfully request directions to a website/document that provides me with propper instructions on how to diagnose and repair "Broken venturi" "cracked venturi nozzle" issues. I have been working with and repairing scientific equipment for a couple of decades know, just give me some good troubleshooting literature and I will fix this....

By the way... Did Ycore ever get his skimmer working properly?

Thanks in advance for your attention to this request. Best rgards..

File this stuff under "stuff happens". Roger will fix you up once you find the source of your skimmer performance issues.

Just remember, UPS, Fedex, USPS aren't paid to be fragile and treat each package like you would handle a baby chick. Things get dropped, tossed, fall off stacks, fall out of trucks, run over, etc.

Have faith!