How Much Substrate Should I Buy For A 75 Gallon Aquarium?

[julielynn47]

I am wondering if anyone could tell me a way to calculate how much substrate I would need, for say and inch and half or 2 inches, in a 75 gallon tank.  I plan on using
 
 
CaribSea Eco-Complete 20 lb bag
 
CaribSea Tahitian Moon Sand 20 lb bag
 
I am wondering how many of each 20 lb bags should I get.  I want to get enough, but not get too much and overspend. 
 
Any help will be appreciated!
 
TIA
 
Oh, and edited to add - is 1-1/2 or 2 inches good for a planted tank?  I really am thinking at least 2 inches or more. Any thoughts on that, that anyone would like to share are appreciated.  My 55 gallon has about an inch and it seems to be very difficult for me to get the plants to stay put. I am wondering how deep it should be so that the plants will have time to take root instead of floating out to the surface.

I just did a google search and found this calculator
 
 
http/www.aqua-calc.com/calculate/gravel-rectangular-solid
 
Seems easy to use.  But I still would appreciate any ideas on a good depth. I don't want it too deep, just deep enough for plants to stay put and fish to root around in and not dislodge the plants....if that is even possible lol

 

[cooledwhip]

Do NOT DO CARIB SEA ECO COMPLETE
 
Its a terrible substrate. I used it and its the worst decision I ever made. So bad substrate and you cant vacuum it. It gets dirty easily.
 
Also usually 1-2 pounds per gallon of tank. So for a 75 gallon tank you would need 75- 150 pounds of sand/substrate. 

 

[Munroco]

I'd say 2 inches at least.

 

[Chad]

It depends on what you are wanting to accomplish and what you are keeping in the tank. I used only 20 pounds in my 75 gallon reef. I wanted it shallow. I had 300 pounds in my 210 gallon. But, I have 10 pounds in my 14 gallon. Each has a different set of livestock and care. The 14 has a sand sifting goby in it so it has more. The reef has corals on the sand bed so I didn't want it deep enough for them to get buried by it. 
 
Advanced Aquarist did a scientific study on substrates that found that tanks in their study group with fine grained substrates had lower phosphates and those with larger, like crushed coral, had higher. 
 
I've used Nature's Ocean Bio-Activ Live Aragonite Reef Sand for most of my tanks. This is great but you have to make sure it's not expired.
The 75 and 14 were started with dry Caribbean reef sand from Bulk Reef Supply. 

 

[julielynn47]

Thanks for all the replies

   I was wanting a substrate under my sand that would be nourishing to plants.  If CaribSea Eco-Complete is terrible, what else is comparable that will be good for plants?
]
Edited to add -- BTW, it will be a freshwater tank. And as of right now all I know for sure that I will have in it are a school of Pictus Catfish.  Also, does anyone else have any opinions on the CaribSea Eco-Complete?   I am interested to know how it works for several people, kind of like weighing the pros and cons of it.

 

[Chad]

For planted I like the Fluval substrate line. But it does need to be replaced periodically. 

 

[Byron]

I also do not recommend Eco-Complete, or Seachem's Flourite which is much the same.  I have had planted tanks for 25+ years, and except for one experiment with Flourite, have only used plain fine gravel or play sand.
 
The problem with EC and Flourite is that they do not seem to provide nutrients (notwithstanding the claims of the manufacturers) unless you also use substrate fertilizer and liquid.  Other users of these products pointed this out to me, and it was necessary.  I found there was no discernible difference in plant growth, plus the sharpness of these substrates is a real problem for substrate fish.  I had to remove my corys when they developed significant barbel and mouth damage (they recovered over play sand).  And the black Flourite always looked (and was) "dirty," as another member mentioned--something I have never seen with my play sand or fine gravel in the past.
 
The other thing to keep in mind if you decide on any two different substrates is that they will mix.  The smaller, i.e., sand, will end up at the bottom with the larger on the top.  I would go with one substrate material.  Which one rather depends upon the intended fish, which are much more important to consider than plants unless you plan an aquatic garden with no fish.  Plants will grow in almost any substrate, though the finer grain substrates are better; plants root more easily, and organics break down better (snails and obviously bacteria do this).
 
I cannot lump some of the other manufacturer's plant substrates into this, as I have never tried them, and some of them might actually do something.  But unless you intend going high-tech, I wouldn't bother.
 
As for the amount, I would aim for about 2 inches depth overall.  I have this in one tank, and less in the others, and all are regular play sand.  For a 75g, presumably with a substrate surface of 48 by 18 inches or thereabouts, two 25kg (50 pound) bags (sand) will provide this, with some to spare (always useful).
 
Byron.

 

[Chad]

I also do not recommend Eco-Complete, or Seachem's Flourite which is much the same.  
 
 

I have to agree, I hate flourite. It was a mess to deal with, didn't facilitate planting at all, and quickly needed replacing. I never used it again. 

 

[julielynn47]

Okay, so, it is just not worth it then. I thought it would be good for the plants. As for the fish, I didn't think it would bother them.  Thanks to both of you on the substrate advice. I need  it...obviously. LOL
 
I want to go with sand, and I would like black sand.  So I guess about 2 inches of just the sand will be good for both fish and plants

 

[julielynn47]

Okay, I am a bit confused on these CaribSea sands.
 
CaribSea Tahitian Moon Sand
Instant Aquarium Tahitian Moon
Instant Aquarium Moonlight
 
I am going to go see if I can figure out the difference, aside from the obvious point or the Instant Aquarium ones having beneficial bacteria already in them...or so I guess.    Moon Sand, Moon and Moonlight... goodness....   Any thoughts?

 

[Chad]

It's probably a slight difference in shade but I'm just guessing. 

 

[eaglesaquarium]

I went with ceramaquartz sand.  Best option was the 'S' grade... very fine.
 
Very good price at a local concrete supply shop.  ~$25 for a 50lb bag.  

 

[Byron]

Okay, I am a bit confused on these CaribSea sands.
 
CaribSea Tahitian Moon Sand
Instant Aquarium Tahitian Moon
Instant Aquarium Moonlight
 
I am going to go see if I can figure out the difference, aside from the obvious point or the Instant Aquarium ones having beneficial bacteria already in them...or so I guess.    Moon Sand, Moon and Moonlight... goodness....   Any thoughts?

 
I avoid products that mess around with bacteria.  For example, the CarribSea Instant Aquarium substrate "immediately begins the cycling process, eliminating new tank syndrome, and discouraging nuisance algaes. Instant Aquarium™ detoxifies metals, eliminates ammonia, neutralizes chlorine and chloramines, and provides a protective slime coat for stressed fish. Instant Aquarium™ also reduces nitrates and nitrites." according to their website.  I would myself not use this; "provides a protective slime coat" bothers me when I don't know how it is doping this (aloe vera, commonly used for this, is dangerous to fish we now know).  And I do not like products that mess about with the nitrifying process...we want that establishing naturally.  If this substrate only adds bacteria, fine (maybe), but it may do more.  And eliminating ammonia is not beneficial as plants need the ammonia/ammonium, though it depends upon just what "eliminates" means.

 

[julielynn47]

Yeah, I don't really care about the Instant thing. I just want black sand.  So maybe I will just go with the Tahitian Moon Sand.
 
 I went to CaribSea's website and one of the sands is not black, the Moonlight one. One is black, and only one of them is just sand, not Instant Aquarium.
 
I have never heard of ceramaquartz.  I will check that out too.

 

[Byron]

Yeah, I don't really care about the Instant thing. I just want black sand.  So maybe I will just go with the Tahitian Moon Sand.
 
 I went to CaribSea's website and one of the sands is not black, the Moonlight one. One is black, and only one of them is just sand, not Instant Aquarium.
 
I have never heard of ceramaquartz.  I will check that out too.

 
One thing I noticed with black is that it is not really black, but a dark grey.  This is because of the light through water.  All substrates will be a different colour/hue in the aquarium from what they are dry in your hand.  But the black under "daylight" for plants turns grey.  The other thing is that it always looks dirty, and it was.  Some don't mind either, but you should know.