Any ideas for a false bottom???

[toi_ss]

Hi, in my upcoming tank build I really want to have a shallow area at the end of the tank for some clams and mangroves as shown in the diagram above. I dont however want a 40cm deep sandbed at that area due to cost, uneven weight and issues with deep sand beds. I want to create a sort of false bottom or fill up the space where the sand would be with a different material. The ideas I have had so far is to either seal it off with silicone and glass but the glass would be very complicated to cut and also I feel that algae would grow there and I wouldn't be able to access it to clean it. I also might be able to use matala mat or some sort of foam that is reef safe that I can use to fill in the space. I can't use coral rubble because it is almost double the price of sand where I live.

 

[Dread Pirate Dave]

Maybe use pond foam to fill in the area? I know others have used it to build rock walls here.

Pond & Stone with Smart Dispenser™

Greatness for the great outdoors. GREAT STUFF™ Outdoor Insulating Foam Sealant is the solution that brings long-lasting, airtight and water-resistant seals beyond the household.

www.greatstuff.dupont.com

 

[toi_ss]

Maybe use pond foam to fill in the area? I know others have used it to build rock walls here.

Pond & Stone with Smart Dispenser™

Greatness for the great outdoors. GREAT STUFF™ Outdoor Insulating Foam Sealant is the solution that brings long-lasting, airtight and water-resistant seals beyond the household.

www.greatstuff.dupont.com

I used to use that stuff to build backgrounds for reptile enclosures, I think I might use coarse matala mat and fill in the edges with expanding foam. Although I don't know how well it will hold up in saltwater - might deteriorate over time

 

[Kens Bees]

Plexiglass and a heat gun? You can make just about any curve or angle you need with a little patience. You’d still need to silicone in place but you would have the area you want.

 

[toi_ss]

Plexiglass and a heat gun? You can make just about any curve or angle you need with a little patience. You’d still need to silicone in place but you would have the area you want.

Yes maybe, if I was to seal it off with a false bottom I would likely just use some glass because one of my friends has a water jet cutter I can use. I just think the empty glass area would grow tonnes of algae and just become a mess.

 

[BeanAnimal]

I don't get the reasoning (at all)

What problems with sand beds?

Uneven weight? Is the tank balancing on something?

What is wrong with no divider, a large piece of rock or two and call it a day?

 

[Troylee]

Personally I’m a diy guy so I’d make it from acrylic or glass… in todays world you could prolly have someone 3D print you that and just silicone it in the tank and call it a day.

 

[toi_ss]

I don't get the reasoning (at all)

What problems with sand beds?

Uneven weight? Is the tank balancing on something?

What is wrong with no divider, a large piece of rock or two and call it a day?

I dont really want to buy 600 lbs of sand just for the end area because im planning on having a 15cm deep end of the tank to grow mangroves in with a fairly deep sand bed, just not 40cm deep because that will cost me around $2000 in sand.

 

[toi_ss]

Personally I’m a diy guy so I’d make it from acrylic or glass… in todays world you could prolly have someone 3D print you that and just silicone it in the tank and call it a day.

Do you think algae would grow in the area underneath the glass false bottom though, if it is just an empty space? I could maybe just cover that area black with something on all sides but i'm not sure.

 

[Troylee]

I dont really want to buy 600 lbs of sand just for the end area because im planning on having a 15cm deep end of the tank to grow mangroves in with a fairly deep sand bed, just not 40cm deep because that will cost me around $2000 in sand.

600 pounds of sand??? Is this like a 15ft long tank? lol… I got 160 pounds in a 300 gallon tank.

 

[Troylee]

Do you think algae would grow in the area underneath the glass false bottom though, if it is just an empty space? I could maybe just cover that area black with something on all sides but i'm not sure.

If it’s sealed water tight and just air inside it then no it can’t grow algae.. no water no algae. It also wouldn’t have light being covered in sand so again no algae. Now bacteria can build up if it’s wet but no algae.

 

[GARRIGA]

Pumice is light and can easily fill the void affordably. Could go as far as adding a diy undergravel filter and increase biological as well.

 

[toi_ss]

If it’s sealed water tight and just air inside it then no it can’t grow algae.. no water no algae. It also wouldn’t have light being covered in sand so again no algae. Now bacteria can build up if it’s wet but no algae.

Okay, thanks for your help. I will likely go and just make it out of glass then. Do you think the false bottom would support the roughly 150 lbs of sand alright?

 

[BeanAnimal]

I dont really want to buy 600 lbs of sand just for the end area because im planning on having a 15cm deep end of the tank to grow mangroves in with a fairly deep sand bed, just not 40cm deep because that will cost me around $2000 in sand.

That makes no sense to me. Volume or cost wise.

It feels like you are in search of a problem to create a complex solution.

Can you please provide the tank dimensions?

 

[toi_ss]

Pumice is light and can easily fill the void affordably. Could go as far as adding a diy undergravel filter and increase biological as well.

I was thinking about just stuffing it with rock but doesnt pumice float? I was thinking if I didn't section it off I would probably use some type of really coarse plastic mat

 

[stephj03]

It might feel like extra work, but I would consider fab'ing an acrylic tray and putting on stilts over a pile of live rock (Stilts either anchored into drilled holes in the rock or through the rock to the floor of the tank.

Even the best seals have some failure rate. If a seam ever failed on a false bottom of this size it would create salinity and nutrient headaches that would be challenging to resolve without a teardown.hth

 

[GARRIGA]

I was thinking about just stuffing it with rock but doesnt pumice float? I was thinking if I didn't section it off I would probably use some type of really coarse plastic mat

Pumice can be soaked and most won't float but if it does then add some reef rubble to hold it down.

 

[toi_ss]

That makes no sense to me. Volume or cost wise.

It feels like you are in search of a problem to create a complex solution.

Can you please provide the tank dimensions?

The tank dimensions are 300x100x65cm and it will be filled to around 50cm deep, there will be a shallow area on one end of the tank that is only 15 cm deep.

 

[EeyoreIsMySpiritAnimal]

Do you think algae would grow in the area underneath the glass false bottom though, if it is just an empty space? I could maybe just cover that area black with something on all sides but i'm not sure.

^^^ This was going to be my suggestion if you were worried about algae

 

[toi_ss]

It might feel like extra work, but I would consider fab'ing an acrylic tray and putting on stilts over a pile of live rock (Stilts either anchored into drilled holes in the rock or through the rock to the floor of the tank.

Even the best seals have some failure rate. If a seam ever failed on a false bottom of this size it would create salinity and nutrient headaches that would be challenging to resolve without a teardown.hth

Probably a good idea, I think I would just do an acrylic box where I would want the empty space to be and then drill some holes to make water be able to pass through it then I would probably put a wavemaker in there to avoid a massive dead zone. Would put the sand in a tray above the box