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bob_nevin

pond leak at skimmer opening

bob_nevin
12 years ago

Just a heads up for older model Aquascape pond owners. Our pond was leaking because the aluminum bolts on the skimmer flange that hold the rubber tight against the skimmer deteriorated. Mostly it was the bolts below the water line. If you have an older Aquascapes pond that has these aluminum bolts, I recommend that you change them.

I fixed the problem by bringing the water level below the skimmer flange and drilling a new hole next to the old broken bolts, that I could not remove since there were no heads left on them. I then replaced them with stainless steel bolts and nuts. I also had to remove the old silicone and re-caulk. Problem solved (it was not as easy to find an fix as I made it sound).

Comments (10)

  • mike_il
    12 years ago

    Even though I have never installed a new Aquascape classic new skimmer I repair probably 10 a year. They start to have problems in four to eight years after being installed. The amount of time they will last is determined by the ph of the pond and the salt content. I do not recommend drilling new holes as you will have the old holes in the liner that can be another source of a leak. If we can not remover the old bolt we use a drill to remove the head of the old bolt. Once the skimmer plate is removed we can usually grab of what is left of the old bolt with a vise grips and remove it. If we can't then we drill the old bolt out and replace them with 1" 1/4-20 stainless steel bolts, nuts, and washers. We remove the old silicone and apply new silicone. The new bolts are installed through the old holes in the liner with a washer and nut on the inside. It takes 12 bolts, washers and nuts on the standard classic skimmer. Usually ponds with this skimmer also have the Aquascape waterfall unit. The same bolts were used in these units. These bolts will usually last a couple of years longer then the skimmer. I usually buy 200 to 300 sets of bolts, washers, and nuts a year. As to why they used aluminum in the first place the response that I have heard was that they want the contractor to have to go back and replace for extra income. But I would guess the real reason was that they would not rust like normal steel and were cheaper then stainless steel. And they didn't know the problem aluminum has when it is in contact with water.
    Mike

  • bob_nevin
    Original Author
    12 years ago

    Thank you for your informative post Mike.

    You stated "These bolts will usually last a couple of years longer then the skimmer." What else happens to the skimmers?

  • mike_il
    12 years ago

    Bob Nevin,
    This was the first skimmer that was made for ponds. It first came on the market in 1995. It has not changed much since it was first introduced. When it was first introduced it used a mesh bag that wrapped around the inside part of the face plate and hung on two screws. The filter pad sat on four PVC pipes that fit into the molded in groves in the front and back wall of the box. The pump was to be installed below the pad with the outlet pipe coming up through the pad and out a hole near the top of the back wall. A bulkhead was mounted in the back wall as an overflow point for the pond. The aluminum bolts that secured the face plate are threaded into aluminum inserts that were put into the skimmer box.
    There have been two changes made to skimmer. The first was to have four slots cut into the top rim of the skimmer. These slots held two aluminum rods that supported the new net. The front rod is shaped so that there is a u that fits around the part of the face plate that is inside the skimmer. The other bar is a straight rod that supports the back of the net. The rods fit in two pockets that are in the net. The later change was replacing the PVC support pipes with a molded rack.
    Now getting onto your question. This skimmer is a mold box that is buried in the ground. It does not have any supports in the box to keep the walls from being deformed. So a lot of times after a period of time I will see the walls of the box deformed from the dirt around it. The second thing is the newer pad rack was put in so that if a horizontal pump was not used it had to be cut up for vertical pump. They did this when they came out with their horizontal pump. There is nothing to keep the U on the front net rod around the face plate. When the debri net gets full the weight tends to bend the rods in removing the net. The last thing is the filter pad has to have a hole cut in it for the outlet pipe to go through. Also if a vertical pump is in the skimmer the pad has to be cut around the body of the pump. The problem is that the holes are hard to get tight around the pipe and pump. So usually the debri gets through the holes rather then getting caught by the pad. And if the holes are cut tight then the debri caught in the pad can block the water from the pump. This can cause the pump to over heat.
    Mike

  • DeputyDogCOPR
    11 years ago

    We had the same leak problem with the same skimmer box today. How long do you need to let the Roof/Flashing Caulk dry before refilling the pond?
    Thanks for your help!

  • Mike56
    11 years ago

    Thanks for the heads up. My skimmer is from 2004 so I will be proactive and replace the bolts this spring.

    Where do you apply the sealer and what kind is it?

  • bob_nevin
    Original Author
    11 years ago

    Mike56
    I used silicone caulk to seal the rubber liner to the skimmer flange. Silicone will not stick to old silicone so you must clean off any old silicone that is on the rubber and simmer flange. I put a 1/4 inch bead around the back ot the flange centered to the bolt holes, also making sure to silicone around the holes. If you do not have stainless steel screws, which is the reason mine rusted, replace them with the same type of screw in stainless steel.
    Hope this helps.

  • Mike56
    11 years ago

    I inspected my skimmer today and was pleasantly surprised. Mine may be an older model or at least a different one. It does not have a nut and bolt through the skimmer wall. It has black Phillips head screws that screw into molded in bumps on the skimmer box. They do not pass through the box at all. Maybe a threaded insert in the bumps? Anyway no rust or corrosion at all :-)
    This skimmer uses the obsolete molded plastic basket with a hinged door built in. I hope it never breaks. I love it!
    Mike

  • goatie
    9 years ago

    Hello,
    I'm another newbie, starting on pond this coming week-end.
    Approx 11ft wide by 15 long and 3 ft deep at the deepest.
    Can someone give me ideas on the best (reasonable priced) skimmer. It's all so confusing....I just want a pond...the mechanical parts aren't fun.
    Thank you So Much.

  • Tracy McMillen
    3 years ago

    i have a pond that is 15 years old. My maintenance company replaced the pump and the valve. Wow! My waterfall is flowing beautifully, but my pond is losing lots of water. Yikes! I turned off the power as a test and within a few days, the pond was 3/4 empty. I’ve scanned the perimeter and have found no moisture. I’m at a loss. The cost of investigation and possible repairs are expensive. I’d love some advice.

  • bob nevin
    3 years ago

    I would check the area where the water enters the skimmer. Check behind the rubber just below the Bottom of the skimmer opening.