DIY Polycarbonate Sump

[karpomatic]

I'm copying my text from the original post on another forum since I'm not allowed to post the link. The original post was from 5/30/20. Enjoy!

I'm going to take a crack at building my own sump for my 125 mostly South American 125 gallon aquarium. I have been using the one in the photo for 3 years now and it's okay but it was originally designed for saltwater and I'm hoping I can do better. The planned dimensions are 48" x 15" x 15", approximately 46 gallons. I'm building it out of 1/4" polycarbonate and sealing it with the Weldon 16. I am basing it on the attached photo I found online. I'm looking for constructive criticism and help only. It's planned for the water from the tank to pour into the socks on the left, flow into 2 or 3 Cer-Media bio filter blocks, then spill over and down thru the vertical section but with 3 levels instead of 2. Cotton batting at the top, volcanic rock, and/or bio-balls. I was thinking of adding another vertical section of 3 levels with more filtration and purigen as the top level. Next it will flow over into the heater section and finally the return pump on the far right.

One of my thoughts is, if I add another vertical section that would flow up then to the heaters, should the water flow under the divider to the pump or still go over spill into the pump section?

**I removed the logos from the sump diagram as it's just used as a reference. **

Skip to 7/20/20 for the next installment.

Well, it took 6 weeks for me to get the correct polycarbonate. I had to reorder since I ordered the incorrect width. Anyway, it took about 13 hours from start to finish. We started with three sheets for 32" x 48" x 1/4" clear polycarbonate. We cut it with a table saw and hand sanded all the edges with multiple grits of fine sandpaper. I'm going to give it 24 hours to set up then it will sit with water in it for a week to check for leaks. I'll also be putting a pump in it to see how it will flow.

 

From 7/21/20 - 

I let the Weldon 4 and 16 cure for 24 hours then added water. I've got a few leaks but nothing too bad. I dried it out and will seal it again after the joints have a chance to dry out.

 

Then on 7/27/20 - 

After fixing the leaks, I let it sit in my garage for the entire week with an 800 gph pump circulating water for a week. Friday night I finally installed it. The entire process took about 4 hours. I also replaced all the tubing. Here is a photo of it up and running.

I am currently using two 200 micron socks but I think they're too fine. They clog up quickly and restrict water flow. I may switch to 300 micron and see how that does.

 

[karpomatic]

On 8/29/21 I took the 125 down and replaced it with a 220 gallon that I resealed. The stand and canopy were custom built my me and my father. I'll post build threads on those as well.

[OnlyGenusCaps]

Thanks for posting this!  I really like the cabinet!  The access panels, including on the side ones, are really sweet.  It looks like you have another thread on that, but I thought I'd mention it here.

Ready for the litany of questions?  Here we go! 

How are you liking the sump?  It looks like you are running single drain lines and then a return through the bottom of dual corner overflows.  Is that a correct interpretation?  I tried to trace the plumbing, but I might have doe so incorrectly.  Is there a reason you chose that configuration for the overflow and return?  I see a lot of bubbles on the return.  How noisy is it?

Did the move to 300 micron socks improve your clogging issues?  It looks like you are running a UV sterilizer that bypasses the bulk of the bio-media.  I've not seen it run this way before.  How is that working out?  Do you like the sterilizer?  Can you tell me the rational for the config on it?

Sorry for all the questions.  I really like the sump, and DIY sumps in general.  I love knowing the thinking that went into the design.  Thanks for humoring me.  And again, nice sump!!!

[karpomatic]

On 1/27/2022 at 9:43 AM, OnlyGenusCaps said:

Thanks for posting this!  I really like the cabinet!  The access panels, including on the side ones, are really sweet.  It looks like you have another thread on that, but I thought I'd mention it here.

Ready for the litany of questions?  Here we go! 

How are you liking the sump?  It looks like you are running single drain lines and then a return through the bottom of dual corner overflows.  Is that a correct interpretation?  I tried to trace the plumbing, but I might have doe so incorrectly.  Is there a reason you chose that configuration for the overflow and return?  I see a lot of bubbles on the return.  How noisy is it?

Did the move to 300 micron socks improve your clogging issues?  It looks like you are running a UV sterilizer that bypasses the bulk of the bio-media.  I've not seen it run this way before.  How is that working out?  Do you like the sterilizer?  Can you tell me the rational for the config on it?

Sorry for all the questions.  I really like the sump, and DIY sumps in general.  I love knowing the thinking that went into the design.  Thanks for humoring me.  And again, nice sump!!!

Don't be sorry. We're all here to help each other. I'll try to answer them in order.

1 - I love using a sump. The maintenance is so easy compared to a canister filter. I've got an FX6 on my 75 and its a great filter but I hate doing the maintenance on it. Yes, I have separate drains per overflow. From my research I was better to do it this way as one drain has a tendency to be more powerful than the other and the pressure could hinder the other drain. The returns are a single pump with the PVC teed to each side. What you can't really see is that the returns are connected at each end to a spraybar that runs across the back of the tank at the water line. I have not been able to do anything about the bubbles, I've tried different configurations on the drains but it didn't change any. It's not terribly noisy.

2 - I ended up taking the socks out and just using filter floss. The socks were restricting the flow to much and starving my pump. I would have been swapping them out every day. I'm running the sterilizer separate so I can slow down the flow thru it. The slower the flow the better the UV works. I purchased a tiny pump that only does about 5gph. With the UV and the temp at about 82° F I've never had a disease. I barely get algae on the glass.

3 - Just something I'd like to add. I'll need to take an updated photo but I have A LOT of biological media in this sump. Two CerMedia blocks, 6 or so bags of volcanic rock, and some ceramic cylinders. Also, 8 bags of Purigen.

[OnlyGenusCaps]

Thank for the reply!

On 1/27/2022 at 9:34 AM, karpomatic said:

I love using a sump. The maintenance is so easy compared to a canister filter.

I also really love sumps.  I've never run a canister, so I don't have a point of reference, but sumps are so flexible and I also like the design aspect of them.  A hand I have perhaps already shown.  🙊

On 1/27/2022 at 9:34 AM, karpomatic said:

Yes, I have separate drains per overflow. From my research I was better to do it this way as one drain has a tendency to be more powerful than the other and the pressure could hinder the other drain.

And you just have the one drain on each side, yes?  Just trying to get a mental image of your setup.  I am drilled for a Herbie overflow.  I'd have loved to do a BeanAnimal, but there just wasn't room in the overflows.  I'm hoping the Herbie will be enough to keep mine running silently.  It sits next to the only TV in the house.

On 1/27/2022 at 9:34 AM, karpomatic said:

I have not been able to do anything about the bubbles, I've tried different configurations on the drains but it didn't change any. It's not terribly noisy.

That's great to hear that even with the bubbles it's not too noisy!  I don't think bubbles are an issue in FW tanks, that seem to be a SW concern.  Plus, yours are at a far end and I'd imagine are dissipated by the time the water gets to the return.  I was mostly curious about the bubbles because I didn't know if the air going down the line was causing undue noise.  Sounds like not, which is great!  I had to fix that on one of my current tanks.  It worked and now it runs silently (well, except for the cheap Chinese return pump, but whatchagonnado?).

On 1/27/2022 at 9:34 AM, karpomatic said:

I ended up taking the socks out and just using filter floss. The socks were restricting the flow to much and starving my pump. I would have been swapping them out every day.

Really?!  Wow!  I've heard about this from so many folks, but so far I've not run into that yet.  Thankfully!  Sorry to hear you did.  That does explain the wad of filter floss I saw in the photo though.  Makes sense!

On 1/27/2022 at 9:34 AM, karpomatic said:

I'm running the sterilizer separate so I can slow down the flow thru it.

Got it.  That makes sense.

On 1/27/2022 at 9:34 AM, karpomatic said:

I'll need to take an updated photo but I have A LOT of biological media in this sump. Two CerMedia blocks, 6 or so bags of volcanic rock, and some ceramic cylinders.

That is quite the assortment!  I'm going to put all my eggs in one K1 sized basket.  We'll see how it goes.