Oversized Skimmer Problems?

DietDr.Kelp

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I can't figure out what the problem is with my skimmer. I have a Deltec MC500 on a heavily stocked SR80. I feel I feed fairly heavily (pellets, fresh and frozen seafood, nori). The skimmer will pull nice skimmate for a few weeks, go crazy when I feed the tank, and then all of a sudden it will produce a lot of micro bubbles, but doesn't actually pull anything into the collection cup. Also no "reaction" to feeding the tank certain foods like it was doing before. I have tried adjusting the amount of air coming through the skimmer, and even when opened fully, nothing will collect once it reaches this "stagnant" phase. However, if I turn the skimmer off and back on it will start pulling skim again. When I turn it off, it needs to sit for an hour or it won't pull air / start properly—maybe the unit simply needs a good cleaning?
Are there any tips or tricks for keeping a slightly oversized skimmer pulling skimmate?
 
I would give it a good cleaning like you suggested. Soak it with citric acid, check the air tube for salt build up, check the impellar for damage.
I guess I should stop being lazy and give it a clean 😛
I've always rinsed gear in white vinegar in the past. Do you think this citric acid looks appropriate / safe? https://a.co/d/j2CmXbp

Thank you!
 
I guess I should stop being lazy and give it a clean 😛
I've always rinsed gear in white vinegar in the past. Do you think this citric acid looks appropriate / safe? https://a.co/d/j2CmXbp

Thank you!
well you can use vinegar, i just use citric acid food grade supposed to be less harsh on pumps and seals but who knows. IT is safe if its food grade Im talking like this or similar brand

Amazon product ASIN B07YNZJX4R
 
well you can use vinegar, i just use citric acid food grade supposed to be less harsh on pumps and seals but who knows. IT is safe if its food grade Im talking like this or similar brand

Amazon product ASIN B07YNZJX4R
I went ahead and ordered a food grade citric acid to try. I've read good things, and now seems like as good a time as any to use it. Hopefully that helps with whatever is going on with the skimmer!
 
well you can use vinegar, i just use citric acid food grade supposed to be less harsh on pumps and seals but who knows. IT is safe if its food grade Im talking like this or similar brand

Amazon product ASIN B07YNZJX4R
I went ahead and ordered a food grade citric acid to try. I've read good things, and now seems like as good a time as any to use it. Hopefully that helps with whatever is going on with the skimmer!
Keep us updated!
 
Update: Finally got around to soaking the skimmer in the citric acid last night. Let it soak for a few hours, rinsed, and returned to the tank. There wasn't much gunk buildup overall, and the pump appeared in good order. Started up very nicely, and has been working well so far! Only time will tell, though. I'll try to remember to come back in a few weeks and make an update of where the skimmer is at.
 
I hope it resolves and works perfectly! What you describe is typical spot on for oversized skimmer, particularly the skimmer neck. A drastically oversized skimmer will not have enough organics to make a stable foam head, then when they build up it will skim as normal and die back down. What tends to happen is if adjusted when "died down" when organics build up enough it will puke out water and overflow. If adjusted when there are enough organics it will skim well but then die down and do nothing for days.

I do hope this isn't the case with your skimmer since there isn't a good solution, but it does fit spot on with what tends to happen.
 
I hope it resolves and works perfectly! What you describe is typical spot on for oversized skimmer, particularly the skimmer neck. A drastically oversized skimmer will not have enough organics to make a stable foam head, then when they build up it will skim as normal and die back down. What tends to happen is if adjusted when "died down" when organics build up enough it will puke out water and overflow. If adjusted when there are enough organics it will skim well but then die down and do nothing for days.

I do hope this isn't the case with your skimmer since there isn't a good solution, but it does fit spot on with what tends to happen.
Thank you for the explanation! I hope this isn't an ongoing problem, but fear it might be the case. It's a little annoying to have to reset every few weeks, but I guess it could be worse.
 

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