Question about sand and plants

[dangerflower]

I'm setting up a new tank soon and I want to use sand as my substrate, which i haven't tried before. I want to use sand because I'm planning on having some corys, because I like the natural look and think it will fit the aesthetic I'm going for, and because I'm doing a botanical style tank with lots of leaf litter and I think all that detritus will work better over sand than gravel. I've read a lot about sand being bad for plants. The tank will be lightly planted, but I am hoping to have some root feeding plants in there (probably amazon swords and dwarf sag).

I was originally considering putting some aqua soil in filter media bags as a base layer and capping this with sand, to provide nutrients, but given that aqua soil wears out eventually anyway, would it make more sense to just use root tabs? 

I'd love to hear anyone's experience with using sand as a planted tank substrate, and any tips or tricks I should know! I'm thinking of using aquarium-specific sand rather than pool filter sand or something, possibly CaribSea.

[Patrick_G]

I like the look of sand too. The tank in my sig has Fluval stratum under pool filter sand. It’s about 7” deep in the back left and tapers to just an inch or two on the right side. I used a few mesh bags to bulk up the deeper part, but just plain aquasoil in the middle and right side. I’ve been told that aquasoil has a high CEC capacity so it’ll hold onto nutrients from the water column even after it loses its initial dose of nutrients. 

[Seattle_Aquarist]

Hi @dangerflower

I've uses sand in planted tanks for several years now.  I can tell you not all 'sand' is created equal. Some is heavy, compacts allowing for a buildup of anaerobic bacteria that can create pockets of sulfur dioxide in the substrate and can result in fish death.  Also, many types of sand have grains of calcium carbonate in the mix which can cause an increase in water hardness and pH.

I use HTH Pool Filter Sand which is >99% pure silicon dioxide which it totally inert and will not affect water parameters.  Also it is a 'light' sand that does not tend to compact like commercial or play sand.  It also has a nice clean white color which makes it easy to see any buildup of detritus. Best of all it isn't that expensive, I pick my HTH sand up at Ace Hardware (if they don't stock it they can order it in and it only costs about $20 for a 50# bag.  -Roy

[Patrick_G]

I use the same sand that Roy does. Good stuff for all the reasons he posted. 

[dangerflower]

@Patrick_G @Seattle_Aquarist Stunning tanks, both of you 😍 This is definitely encouraging!

That pool filter sand is about half the cost of the aquarium sand I was considering so that certainly seems worth looking into. How fine are the grains? Does it need a ton of rinsing before being used?

[Patrick_G]

On 9/29/2022 at 6:36 PM, dangerflower said:

@Patrick_G @Seattle_Aquarist Stunning tanks, both of you 😍 This is definitely encouraging!

That pool filter sand is about half the cost of the aquarium sand I was considering so that certainly seems worth looking into. How fine are the grains? Does it need a ton of rinsing before being used?

Small Panda Cory for scale. The black bits are Fluval stratum that pops up to the surface from time to time. The sand looks yellowish in the pic but it’s actually much lighter like in Roy’s pic. 

[Seattle_Aquarist]

On 9/29/2022 at 6:36 PM, dangerflower said:

@Patrick_G @Seattle_Aquarist Stunning tanks, both of you 😍 This is definitely encouraging!

That pool filter sand is about half the cost of the aquarium sand I was considering so that certainly seems worth looking into. How fine are the grains? Does it need a ton of rinsing before being used?

Hi @dangerflower

The HTH Pool Filter Sand has fine, uniform sized grains.  No rinsing, in fact here is that same 75 gallon after I filled it without any rinsing whatsoever.

Here is how I filled tj 75 gallon tank to avoid causing a lot of particulates in the water.  Wax paper, plate, slow fill with hose


And here it is immediately after filling.  Hope this helps!  BTW, you have a good aquarium club in Portland, the Greater Portland Aquarium Society and two of my favorite aquarium shops. The Wet Spot and World of Wet Pets!  -Roy

Edited September 30, 2022 by Seattle_Aquarist

[Beardedbillygoat1975]

I second and third @Seattle_Aquaristand @Patrick_Gthe HTH is awesome. I’ve been picking up Stratum on sale from the big box shops when I can. This along with the pool filter sand will form the backbone of my wife’s 60 gallon planted tank. Diana Walstad has been using it to cap her dirted tanks for a couple decades. You can also look up Father Fish and he has a guide if you want to go cheap his Walstad tank is it. 

[Tanked]

My Wisteria and PSO are growing in the the project tank.  An inch and a half of pool sand and questionable lighting seems to suit them.  They won't grow in the other tanks.

Especially now that fall is coming, the pool and grill stores may cut you a better deal if you take the broken bags off of their hands.

[JettsPapa]

On 9/29/2022 at 7:57 PM, dangerflower said:

. . . I've read a lot about sand being bad for plants. 

Don't believe everything you read.

On 9/29/2022 at 8:36 PM, dangerflower said:

@Patrick_G @Seattle_Aquarist Stunning tanks, both of you 😍 This is definitely encouraging!

That pool filter sand is about half the cost of the aquarium sand I was considering so that certainly seems worth looking into. How fine are the grains? Does it need a ton of rinsing before being used?

I've used two different brands of pool filter sand (don't remember the names).  I haven't rinsed either one.  One of them didn't cause any cloudiness when I filled the tank, and the other one only had a small amount that was cleared up the next day, so I don't consider that a big enough issue to bother with cleaning.

I get mine from pool supply stores.  I saw some at one of the big box home improvement stores, but the label said it has some kind of special additive.  It didn't give specific information on that additive, and the brand name of the pool filter sand was Clorox, so I was concerned about using it in a fish tank and buy it.

I use Black Diamond sandblasting sand from Tractor Supply when I want a darker substrate.  It does need a considerable amount of rinsing.

[Patrick_G]

I think it’s always a good idea to use a system like Roy’s when filling a new tank. Fill it very slowly with a ceramic dish and a diffuser. That way you’ll avoid the initial cloudy water phase. 

[DaveO]

I love sand for substrate, and so do the plants. I think you are on the right track looking at CaribSea brands. The Super Naturals line has many natural looking blends. I chose Piece River. I don't mind the extra cost of CariSea because it will be used and enjoyed for many years. Here's a tank I through together a few months ago using nothing but clippings and extra plants I yanked out of other tanks. 

[dangerflower]

Thanks for the help, everyone! I decided to try the pool filter sand - I found the last bag of HTH at my local Ace. It's really nice sand. I was expecting it to just be white but it actually looks very natural. @Seattle_Aquarist I used your trick with the plate and wax paper to fill the tank and it worked perfectly! Very little cloudiness.

[Seattle_Aquarist]

Glad to hear you like it @dangerflower.  If it starts to look 'dirty' just siphon off the top 1/8" or so then rise some new sand in a bucket and add it slowly by hand.  -Roy