How to clean between overflow layers? Please help, Thank You

NCHornet

Jack Dempsey
MFK Member
Apr 27, 2012
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I recently purchased one of the tanks that I have always wanted. It’s a star fire 220 gal glass tank that was only a couple months old when the previous owner came back from a cruise to a horrific smell in his home. The return pump in the sump died and so did everything living in the tank. It was setup as a reef tank and he lost thousands of dollars of corals, frags, fish and live rock. The person decided to throw in the towel and I took it off his hands. I am going to use this tank and sump for a heavily planted discus tank.

The tank has 2 overflow boxes and these overflows have an outer layer and an inner layer with a space between them about a quarter of an inch in width, The inner is silicone to the back glass the full length of the box and so is the outer layer. The outer is also sealed to the bottom of the tank as well. Since this tank was used for saltwater it has all the calcium scale deposits in the gap between these layers. How am I supposed to clean this area and get rid of these deposits? I have seen overflow boxes that open like a hinge door for cleaning but these aren’t like this. Only way that I can see to do this is to cut the seal around the outer layer, down both vertical edges and then across the bottom. However there is still a problem with this method. Looking down at the gap between the outer and inner layers there are spacers down the center every 6 inches or so to maintain the space between them. There are no screws or other visible fasteners holding these spacers in place. It appears to be glued or plastic welded which means separating these 2 layers isn’t going to be easy, breaking something is definitely possible. I must be missing something because nobody would design overflow boxes like this. Within a year the space between these layers would be filled solid with deposits if doing a saltwater. These deposits are like concrete too. I’m going to cap the holes at the bottom of the overflows and fill them with vinegar and water solution. Hopefully that will make removing these deposits possible? But what would you do if you had the tank up and running and you needed to clean this area out? If you look at the pic that shows the slots in the outer layer at the bottom appear to be pretty much blocked by these deposits. Any help would be much appreciated, Thanks
Kevin

IMG_20191120_172731.jpg
In the above pic you can see the deposits between the 2 layers and also the spacer in the middle that is bonded to at least the inner layer.




IMG_20191120_173644.jpg


The inner layer is attached to the back glass in exactly the same way.


IMG_20191120_173542.jpg

The pic above shows the bond between the outer layer and the bottom of the tank as well as the slots being almost fully blocked by these deposits. I keep thinking I must be missing something right in front of my face, but what??????? Thanks for any help and/or advice.
NCH

 

esoxlucius

Redtail Catfish
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Dec 30, 2015
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That does look like a really bad DIY job by someone who didn't put a lot of thought into what they were doing. It's the black silicon that gives it away for me. The third picture shows the tank seam silicon being the usually clear material and the overflow box silicon is black! So I don't think the tank makers did it. It wouldn't have been so bad if the inner sleeve was removable but that too looks siliconed in.

You've no real way of getting anything down that gap to clean, and those deposits, as you mentioned, will be very hard and stubborn to shift.

I think the only way is to start over and rip it out. Put a better one in.
 
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twentyleagues

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1 that tank has been running for a while not a couple of months. Best way to clean that stuff is vinegar and water. Unfortunately it's a very large tank. I have done this on a ton of tanks. Fill the tan with water may need to be actually running in some cases (yours). Put vinegar in the water. It will disolve the calcium build up. Probable going to need 2 gallons on your tank. My .02 on the overflow it could still be factory. Aqueon does that all the time the 90 I had was like that same overflow and all clear silicone except where the overflow is. Its almost like an after thought "oh! We are going to make this one reef ready". It seems its only on their tanks that are not corner overflow. Come to think it may have been the 75g.....?
 

TheWolfman

Potamotrygon
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I was at my lfs today looking at a aquaneon tank with the same overflows same black silicone on the overflow but not on the tank. Good idea to tape up the weir and fill the space with vinegar.
 
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NCHornet

Jack Dempsey
MFK Member
Apr 27, 2012
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41
36
NC
Thanks for the replies and for the advice. The 2 months is what I was told but it's not really important, the crud in there is. I sure would have thought Aqueon wouldn't of done something so stupid. I know filling the boxes willsoften the crux up to make it easier to clean but the problem is still there. Freshwater won't create the same deposits but it's still going to be a trap for plant matter and everything else that can send ammonia levels sky high. I'm going to try and separate the 2 layers and only use the outer one. If this doesn't work I will have to replace the overflow boxes. If this is the case is there one that is better than the others? Thanks again for the help. Later
NCH
 

twentyleagues

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The two layers is to pull from the bottom too. The newer models come with a removable front cover. That tank and design is older. Is there a tag on the bottom trim center brace. If so it will tell you the build date.
 

NCHornet

Jack Dempsey
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Apr 27, 2012
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I can look when I get some help to turn it over, but it won't change what I'm dealing with now and it's just a huge mess and a piss poor design, especially for a reef tank. Later
NCH
 

twentyleagues

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Usually you can see it through the glass no need to flip the tank. Occasionally it's under the top rim on the back also visible through the glass. Anyway really doesnt matter I think you will be hard pressed to find a prebuilt overflow that will work as well. Ever do any acrylic work? Table saw, router, clamps and some Weldon and acrylic of course home made overflow.
 

NCHornet

Jack Dempsey
MFK Member
Apr 27, 2012
51
41
36
NC
I'm a custom cabinet maker so building one isn't an issue. I think I will try and seal off one of the over flows and fill with vinegar and water and see if I can get that stuff out. Going fresh water means this scale deposits won't exist. But it still would be a space that could again fill with plant matter and other crap and cause serious cycle issues. I haven't found any overflows that have a removable panel. If I could locate a couple replacing them would be a simple thing to do. Thanks for the help and advice. Later
NCH
 
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