Foam under acrylic sump?

fltekdiver · 06/05/2018, 07:32 PM

I bought an acrylic sump and I can only find a few threads where people use Styrofoam or rubber to put under the sump.

I've read you can have mold issues if you cover the whole bottom of the sump with either?

I'm ready to plumb in the sump but stuck on what to use under it

Thank you for the help

Scotch_c · 06/05/2018, 09:14 PM

Don’t need it. Pain in the *** to replace and nearly useless IMO. use a flat piece of wood if you need any flat surface area.

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ca1ore · 06/05/2018, 09:53 PM

Ask the manufacturer what they recommend. I always put foam under my acrylic sump (when I had one). Cannot really see why it would exacerbate mold.

uclamatthew · 06/06/2018, 09:40 AM

I don't think you need it, but I guess to each their own.

reeftivo · 06/06/2018, 10:15 AM

i always use foam as well.

my experience is that it decreases the resonant pump hum that can occur. no mold issues to date.

FullBoreReefer · 06/06/2018, 11:27 AM

I’d ask the manufacturer.

About 9yrs ago I had a glass tank built, although you are referring to an acrylic sump, but, the manufacturer I chose insisted I use foam under the display to abide by their warranty.

Just a thought

fltekdiver · 06/06/2018, 01:15 PM

Thanks it's a Fiji Advanced 20 sump

I will look on their website to see if I can find anything

If I did decide to put a piece of foam the you put a thin piece or are you using something like a quarter inch?

reeftivo · 06/06/2018, 05:23 PM

1/4 inch is fine

fltekdiver · 06/06/2018, 05:30 PM

I built a brand new stand, however the bottoms not perfect.

I think I would feel better with some foam.under it, and that will help with pump noise

yacn · 06/07/2018, 06:56 AM

I cut and installed 1/2" Polyisocyanurate Rigid Foam Insulation Board sold at home depot under both my all glass 150 display tank, and my 40 gallon acrylic sump. Both DT and sump sit on plywood base that covers entire footprint...not just around the edges like some stands do.

11+ yrs .... no mold or any other issues to date

AC_Rhino · 06/07/2018, 07:41 AM

I think you'd have other issues if you are getting enough water outside of your DT and sump to cause mold to grow.

timnem70 · 06/07/2018, 09:10 AM

Just put a drip pan under it. Wish I would of. Just easier to siphon if a spill.

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luisgo · 06/07/2018, 12:03 PM

I use a rubber mat under my sump, under my calcium reactor, under my pumps, etc. The rubber decreases vibration noise. This is my Iwaki pump with double rubber mats.

saveafish · 06/08/2018, 01:15 PM

Ive used the white pvc board from Home Depot in the past and will be using it on this build as well.

fltekdiver · 06/08/2018, 07:20 PM

Starboard ?

tkeracer619 · 06/10/2018, 04:51 PM

You gotta work pretty hard to get mold from saltwater. Salt is a preservative, mold has a hard time growing in it.

That said, typically you don't use foam under acrylic. It should go on top of a flat hard surface. To be honest unless the sump is under built it will be fine on any flat surface.

The issue with foam or not is based on the concept that the tank will settle on the foam. Glass tanks can't deflect so if they go on a surface that also cannot deflect and isn't flat you end up with pressure points or a situation that rips the silicone seams apart. With acrylic on foam since the acrylic can deflect it puts stress into the entire tank as it fills and deforms. The absolute worst thing you can do is install the tank/sump in such a way that it twists when loaded. This will break any type of tank.

There are companies that go against the grain but typically...

-Flat bottom glass tank without trim with walls on top of bottom = foam
-Rimmed glass tank - no foam
-Rimmed glass tank with bottom floating between side panes = no foam
-Acrylic = no foam

If the stand top surface is not flat it should be sanded flat. Shims are used between stand and floor.

Doing anything else is at your own risk or by manufacturers direction.

fltekdiver · 06/12/2018, 02:18 PM

Thanks for the feedback I ended up picking up
Starboard and putting it under the sump and ATO

I cut a piece to fit the entire length on the to stand it is perfect with no imperfections

I appreciate everybody's feedback you guys are awesome

06/05/2018, 07:32 PM	#1
fltekdiver Registered Member Join Date: Feb 2013 Posts: 1,533	Foam under acrylic sump? I bought an acrylic sump and I can only find a few threads where people use Styrofoam or rubber to put under the sump. I've read you can have mold issues if you cover the whole bottom of the sump with either? I'm ready to plumb in the sump but stuck on what to use under it Thank you for the help __________________ RedSea Reefer 350 ,Apex Controller ,2x Hydra 26HD lights Reef Octopus eSsence S-130 Protein Skimmer Reef Octopus VarioS return pump , UV sterilizer Ice Cap 3K Gyre - Started up 8/13/19

06/05/2018, 09:53 PM	#3
ca1ore Grizzled & Cynical Join Date: Apr 2006 Location: Stamford, CT Posts: 17,319	Ask the manufacturer what they recommend. I always put foam under my acrylic sump (when I had one). Cannot really see why it would exacerbate mold. __________________ Simon Got back into the hobby ..... planned to keep it simple ..... yeah, right ..... clearly I need a new plan! Pet peeve: anemones host clowns; clowns do not host anemones! Current Tank Info: 450 Reef; 120 refugium; 60 Frag Tank, 30 Introduction tank; multiple QTs

06/06/2018, 09:40 AM	#4
uclamatthew Registered Member Join Date: Dec 2009 Posts: 49	I don't think you need it, but I guess to each their own. __________________ Planning newest tank... Red Sea XL 425, dual MP40QDs, dual Vectra M1 return pumps, custom fuge in sump, Apex controller, lights, etc. TBD

06/06/2018, 10:15 AM	#5
reeftivo Skim junkie Join Date: May 2008 Location: chino, CA Posts: 3,417	i always use foam as well. my experience is that it decreases the resonant pump hum that can occur. no mold issues to date. __________________ I told you not to be stupid you moron!(Stern) Current Tank Info: 60 gal cube/20g tideline sump-mixed reef, Aquamaxx c-tech Ca Rx, Akula 160 skimmer, paxbellum N18, mitras LX7 lighting with T-5s, apex controller

06/06/2018, 11:27 AM	#6
FullBoreReefer Registered Member Join Date: Jul 2010 Location: Wooster, OH Posts: 1,862	I’d ask the manufacturer. About 9yrs ago I had a glass tank built, although you are referring to an acrylic sump, but, the manufacturer I chose insisted I use foam under the display to abide by their warranty. Just a thought __________________ 60x36x24 mixed reef. 40b sump. Regal 250int Varios. 4xHydra26HDs+t5s. 4xMp40wes. Apex2016.

06/05/2018, 09:14 PM	#2
Scotch_c Registered Member Join Date: Mar 2017 Posts: 196	Don’t need it. Pain in the *** to replace and nearly useless IMO. use a flat piece of wood if you need any flat surface area. Sent from my iPhone using Tapatalk

06/06/2018, 01:15 PM	#7
fltekdiver Registered Member Join Date: Feb 2013 Posts: 1,533	Thanks it's a Fiji Advanced 20 sump I will look on their website to see if I can find anything If I did decide to put a piece of foam the you put a thin piece or are you using something like a quarter inch? __________________ RedSea Reefer 350 ,Apex Controller ,2x Hydra 26HD lights Reef Octopus eSsence S-130 Protein Skimmer Reef Octopus VarioS return pump , UV sterilizer Ice Cap 3K Gyre - Started up 8/13/19

06/06/2018, 05:23 PM	#8
reeftivo Skim junkie Join Date: May 2008 Location: chino, CA Posts: 3,417	1/4 inch is fine __________________ I told you not to be stupid you moron!(Stern) Current Tank Info: 60 gal cube/20g tideline sump-mixed reef, Aquamaxx c-tech Ca Rx, Akula 160 skimmer, paxbellum N18, mitras LX7 lighting with T-5s, apex controller

06/06/2018, 05:30 PM	#9
fltekdiver Registered Member Join Date: Feb 2013 Posts: 1,533	I built a brand new stand, however the bottoms not perfect. I think I would feel better with some foam.under it, and that will help with pump noise __________________ RedSea Reefer 350 ,Apex Controller ,2x Hydra 26HD lights Reef Octopus eSsence S-130 Protein Skimmer Reef Octopus VarioS return pump , UV sterilizer Ice Cap 3K Gyre - Started up 8/13/19

06/07/2018, 06:56 AM	#10
yacn Registered Member Join Date: Nov 2007 Location: Detroit, Michigan Posts: 212	I cut and installed 1/2" Polyisocyanurate Rigid Foam Insulation Board sold at home depot under both my all glass 150 display tank, and my 40 gallon acrylic sump. Both DT and sump sit on plywood base that covers entire footprint...not just around the edges like some stands do. 11+ yrs .... no mold or any other issues to date

06/07/2018, 07:41 AM	#11
AC_Rhino Registered Member Join Date: Aug 2017 Posts: 66	I think you'd have other issues if you are getting enough water outside of your DT and sump to cause mold to grow.

06/07/2018, 09:10 AM	#12
timnem70 Registered Member Join Date: Apr 2015 Posts: 462	Just put a drip pan under it. Wish I would of. Just easier to siphon if a spill. Sent from my LG-LS997 using Tapatalk

06/08/2018, 01:15 PM	#14
saveafish Registered Member Join Date: Sep 2006 Location: indiana Posts: 873	Ive used the white pvc board from Home Depot in the past and will be using it on this build as well. __________________ If it was'nt for the sea I could not see or sing ( Jimmy Buffet ) I like to glue animals to rocks and put disturbing amounts of electricity and saltwater next to each other Reefing is'nt how long you been in it. It is how deep you get in it. Current Tank Info: 400g display build, 300g sump, 75g ATO, 75g refug and a few more. Close to a 1000g. 200g mixing station.

06/08/2018, 07:20 PM	#15
fltekdiver Registered Member Join Date: Feb 2013 Posts: 1,533	Starboard ? __________________ RedSea Reefer 350 ,Apex Controller ,2x Hydra 26HD lights Reef Octopus eSsence S-130 Protein Skimmer Reef Octopus VarioS return pump , UV sterilizer Ice Cap 3K Gyre - Started up 8/13/19

06/10/2018, 04:51 PM	#16
tkeracer619 Registered Member Join Date: Jan 2006 Location: Westminster, CO Posts: 17,289	You gotta work pretty hard to get mold from saltwater. Salt is a preservative, mold has a hard time growing in it. That said, typically you don't use foam under acrylic. It should go on top of a flat hard surface. To be honest unless the sump is under built it will be fine on any flat surface. The issue with foam or not is based on the concept that the tank will settle on the foam. Glass tanks can't deflect so if they go on a surface that also cannot deflect and isn't flat you end up with pressure points or a situation that rips the silicone seams apart. With acrylic on foam since the acrylic can deflect it puts stress into the entire tank as it fills and deforms. The absolute worst thing you can do is install the tank/sump in such a way that it twists when loaded. This will break any type of tank. There are companies that go against the grain but typically... -Flat bottom glass tank without trim with walls on top of bottom = foam -Rimmed glass tank - no foam -Rimmed glass tank with bottom floating between side panes = no foam -Acrylic = no foam If the stand top surface is not flat it should be sanded flat. Shims are used between stand and floor. Doing anything else is at your own risk or by manufacturers direction. __________________ Hobby Experience: 9200ish gallons, 26 skimmers, and a handful of Kent Scrapers. Current Tank: Vortech Powered 600G SPS Tank w/ 100gal frag tank & 100g Sump. RK2-RK10 Skimmer. ReefAngel. Radium 20k. Last edited by tkeracer619; 06/10/2018 at 05:02 PM.

06/12/2018, 02:18 PM	#17
fltekdiver Registered Member Join Date: Feb 2013 Posts: 1,533	Thanks for the feedback I ended up picking up Starboard and putting it under the sump and ATO I cut a piece to fit the entire length on the to stand it is perfect with no imperfections I appreciate everybody's feedback you guys are awesome __________________ RedSea Reefer 350 ,Apex Controller ,2x Hydra 26HD lights Reef Octopus eSsence S-130 Protein Skimmer Reef Octopus VarioS return pump , UV sterilizer Ice Cap 3K Gyre - Started up 8/13/19