Non drilled tank alternatives- My DIY overflow...

Salt...
The 90 on top of the vent pipe serves 2 purposes.
1. - It 'hangs' the overflow on the back of the tank well, by the 2 contact points.
2. It's not glued, and I can take the cap with the whole in it off and turn it facing up and poiur water in it to get the water in the bottom loop before yhou start your siphon.

It has nothing to do with back flow in this case.

I'll make a few comments on your next post there.

 

I like you photos and your DT is looking good.
I think we discussed the potential problems when you have 2 overflows

My 'intank overflow' was painted black, and quickly was covered in corrilline. I also have some rocks and corals stacked up by it also.

The problem with the holes you have drilled near the top, is that the water tends to get pulled in from those holes under the waters surface, and you have greatly reduced your surface skimming at that point.
The surface skimming seems to be very important in gas transfers and other waste issues. In a nutshell, surface skimming is preferred, the larger area the better.
You may also have trouble keeping the water surface linside the bottom of the top trim, so you'll see a gap when viewing.
ALSO- now you have potentially more water volume that will drain down in a power out- I hope you tested this several times to keep from overflowing your sump on a power out.

The sponges- I too tried this for a short time!
I found that they clog easily- which becomes a nitrate factory and also raises the water level in the tank. I now use media bags in the top shelf of my overflow, and it keeps it real quiet. I clean about every 10 days.
The loudest thing on my system is the fans form the LED's, and they are opretty quiet too! My DT is in my fanmily room, where we have get togethers, bible studies, etc., and it's never a problem with noise.

The Ball valve after the overflow/before the sump.
I found this served NO practical purpose. I always left it open anyways.
With this type of overflow, you can't use that vavle to quiet down the flow- this promotes a DT overflow- that will happen.
I also thought I would use it when I worked on things.
But think about it- you're not going to turn it off while the return pump is on- overflow the DT.
And when you shut down the return pump, the overflow stops flowing-right? It does keep water in the outer and inner and top loop however, so it is already running again without repriming after a power out.
Really that is a obsolete place for a ball valve.

I think putting a valve on the return pump is a smart, good thing- especially when the return pumps output to the system is close to maxing out the flow of the overlfow/sump return.

I hope this helps- keep the thoughts, ideas, variations coming!

Todd

 

Tank looks pretty good man. I like the stand setup too. metal frame with wood covering. if possible i would suggest being able to easily remove of lift all four sides for easy access just a problem i have with my stand.
I dont mind the look of my pipe it is custom which i like and black other than the top bowl. so no big deal
also idk bout stacking rocks against it :/ or against the glass in back lol maybe next time i 're-rockqua-scape' i will try and find some new small rock to stck around it
the sound that is most noticeable isn't the overflow part it is the drop from top of tank to the bottom of the U it shouldn't be this part but it is for some reason.
i had a sponge in my 'bowl for a day and it was filled with crap already so i dont want to do that. I have a filter sock on my intake on my sump/fuge to filter some particles

 

Hey, building a larger diameter system as mine has stopped working as efficiently since taking it off of my tank and putting it back on. I am going to try and figure out why it isn't working after that.
I have it ready to be measured and placed in the tank once the glue dries... well I am going to go the beach and get some crushed coral first and cover the giant 65mm overflow tube with crushed coral instead of painting it black. I think this will add a little character and make the tube less ugly than grey but more attractive than black

 

If there is some air in the tip loop, and/or debris in the smaller tubes- that can restrict the flow some.
Is the return pump putting out the same volume? then is the DT rising, about to overflow? If not, it's yhour return pump, not the overflow drain.

MY intank overflow got covered in coralline algae like my back wall in a few months.
The CC sounds good too

In your pic, your tank looks very young, but it looks Good!

 

yea. my tank just cycled a few weeks ago.
here are some pix of my new overflow.
I added a pump to pump water into the overflow and its being less loud. so I guess that leads me to wonder how do i get more flow INTO the overflow without overflowing the tank and still have the guard on the to prevent lost fishies?
wont upload images for some reason

 

You can cut out some eggcrate for the top.

I use a vinyl gutter guard. I cut it up to fit and bend it around the pipe. It bends and has large holes

 

vinyl gutter guard sounds like a good idea if i can find it here.
buuuut this noise is drivving me nuts now its getting air from air vent i assume.
but i can see the air get into the flex pipe that goes into the sump
its making me sad lol.

 

With this type of overflow, it''s going to pull air into the sump wia the air vent tube. This basically has to happen so it can self regulate differences in flow into the intank overflow.
Mine pulls alol kinds of asir into the sump at the sumps return from the overflow. Use a filter sock, or chambers to dissipate it.

 

I understand there will be some air and some noise... fine. BUT it sounds like I have a washing machine in my living room... not pleasant... im about 2 days from ordering a HOB ... and I dont wanna do that lol.

i KNOW it can be quieter cause the 20mm setup I had was much quieter. still had some noise but not like this. i DONT wanna go back to that one cause I have alot more flow with this one. problem is simply well the flow through the sump is so much greater that the water is actually 'charging' over the baffles instead of slowly flowing over (good portion of noise - and not overflow related)
BUT the washing machine noise comes from the drain pipe when it hits the sump. it will be running fine then get a RUSH of water like it finally got full siphon. I KNOW it is able to suck enough water cause the water is up to the bottom of the cup.
it doesn't have to travel around 90o turns now as it is in a flex hose from the T to the sump.

I love the design and have suggested it to people before. i just wish i cold have the flow I hvae without the extra noise.


WELLLLL

I FIXED IT
lol.
the flex tube I used was such a tight fit over the ribbed cone from the 35mm that it wasn't allowing the full flow through. (the reason I used that tube is cause it was clear with thread in it and a stronger hose less likely to kink. HOWEVER now I have a hose that can allow full flow or at least at this moment in time it does. now just a few small noises. MUCH quieter lol.
sorry I didn't think of it sooner. but I hope this helps someone in the future.
now to get the gutter cover stuff so i can have a little better overflow rate.