How much LR?

jriechel · 03/10/2008, 09:01 PM

I know the rule of thumb of 1-2lbs LR per gal. However, there are so many variables, that I find this rule to be ambiguous at best. For instance, the porosity, the permeability, and the size of the pieces themselves all should affect the amount of bacteria, hence the biological filtering capacity of a given quantity of LR. Further complicating things is how the rock is placed in the tank. Piles seem to be popular and effective. But I have also read with interest the use of acrylic rods to stack LR, as well as using vertically placed large-diameter PVC upon which rocks are hung with a very natural appearance. Proponents of these last two methods submit that water flow reaches all surfaces and therefore necessitates a much lower rate of LR needed for the same amount of filtration as the traditional pile.

So what gives? How is a rank beginner to know how much LR to use? For that matter, does anyone know the relative rates of biological filtration of LR, or are all these stocking schemes more art than science?

BLKTANG · 03/10/2008, 09:06 PM

DP

BLKTANG · 03/10/2008, 09:08 PM

your LR ammount soley depends on the size if the skimmer you are going to use,the bigger the skimmer the less LR you can get away with.It all comes down to nutrient import,& export.I have 50lbs in my 75,& 14 fish.But wet skim with a skimmer rated for 250g.My sump is new technology too.I like the open aquascape.Gives more room for my fish to swim.

demonsp · 03/10/2008, 09:09 PM

2 lbs per gallon to much. 1 lb per gallon is great as you will add more as you add frags. Then if its a new setup then a good mix of base rock and LR is better and less expensive. You want space for water flow and CUC to get all around.

Tswifty · 03/10/2008, 09:15 PM

Very well thought out, intelligent post...

My guess is that this "magic number" does not really exist, and is dependent upon many things... Livestock will be a large factor... larger fish = ample open space requirements = less LR... Most people seem to stock LR according to their aquascaping needs and preferences, then once done they are usually within the 1-2 lb limits. Plus LR can also be stored in the sump/fuge to boost bioload. Another debate much like this is the "proper" depth for a sand bed.

You'll find out that many things in this hobby are ambiguous at best...

I personally am around the 2lbs per gallon mark which includes the LR in my refugium, and I utilize a 2-3" sand bed in my display, and a 4-5" in my refugium along with cheato.

demonsp · 03/10/2008, 09:25 PM

There are so many varibles and to keep it simple start small. The minimum of 1 lb per gallon for less trouble.The more rock you have the more flow and feeding rutine and maintance are needed.

tmz · 03/10/2008, 09:36 PM

You have answered your own question. It is more art than science and something folks like to argue about.1lb 2lbs 3 4. More is better ?less is more. Where will the fish swim?Biolaod, skimmer, sand bed y/n. I've seen sucessfull reefs with 1/2lb per g and some with over 2lbs per gallon.

demonsp · 03/10/2008, 09:39 PM

My main point is to start with the minimum.If you have trouble then ruleing out the amount of LR would be nice. Get the basics in order and then start adding.

03/10/2008, 09:01 PM	#1
jriechel Registered Member Join Date: Feb 2008 Location: Snohomish, WA Posts: 41	How much LR? I know the rule of thumb of 1-2lbs LR per gal. However, there are so many variables, that I find this rule to be ambiguous at best. For instance, the porosity, the permeability, and the size of the pieces themselves all should affect the amount of bacteria, hence the biological filtering capacity of a given quantity of LR. Further complicating things is how the rock is placed in the tank. Piles seem to be popular and effective. But I have also read with interest the use of acrylic rods to stack LR, as well as using vertically placed large-diameter PVC upon which rocks are hung with a very natural appearance. Proponents of these last two methods submit that water flow reaches all surfaces and therefore necessitates a much lower rate of LR needed for the same amount of filtration as the traditional pile. So what gives? How is a rank beginner to know how much LR to use? For that matter, does anyone know the relative rates of biological filtration of LR, or are all these stocking schemes more art than science?

03/10/2008, 09:06 PM	#2
BLKTANG Registered Member Join Date: May 2005 Location: Never,Never Land Posts: 7,061	DP __________________ We the few have done so much,for so long,for so little.That we are now qualified to do anything with nothing. ____________________________________________________________________________ Current Tank Info: RR 90 Maganvore sump,250w Hamilton fixture,VorTec's ASM skimmer.

03/10/2008, 09:08 PM	#3
BLKTANG Registered Member Join Date: May 2005 Location: Never,Never Land Posts: 7,061	your LR ammount soley depends on the size if the skimmer you are going to use,the bigger the skimmer the less LR you can get away with.It all comes down to nutrient import,& export.I have 50lbs in my 75,& 14 fish.But wet skim with a skimmer rated for 250g.My sump is new technology too.I like the open aquascape.Gives more room for my fish to swim. __________________ We the few have done so much,for so long,for so little.That we are now qualified to do anything with nothing. ____________________________________________________________________________ Current Tank Info: RR 90 Maganvore sump,250w Hamilton fixture,VorTec's ASM skimmer.

03/10/2008, 09:15 PM	#5
Tswifty Registered Member Join Date: Sep 2007 Location: PA Posts: 14,022	Very well thought out, intelligent post... My guess is that this "magic number" does not really exist, and is dependent upon many things... Livestock will be a large factor... larger fish = ample open space requirements = less LR... Most people seem to stock LR according to their aquascaping needs and preferences, then once done they are usually within the 1-2 lb limits. Plus LR can also be stored in the sump/fuge to boost bioload. Another debate much like this is the "proper" depth for a sand bed. You'll find out that many things in this hobby are ambiguous at best... I personally am around the 2lbs per gallon mark which includes the LR in my refugium, and I utilize a 2-3" sand bed in my display, and a 4-5" in my refugium along with cheato. __________________ "Enough light? Heck I could go barebottom and grow SPS in the stand!" - DiscoReefRover

03/10/2008, 09:36 PM	#7
tmz ReefKeeping Mag staff Join Date: Apr 2006 Location: West Seneca NY Posts: 27,691	You have answered your own question. It is more art than science and something folks like to argue about.1lb 2lbs 3 4. More is better ?less is more. Where will the fish swim?Biolaod, skimmer, sand bed y/n. I've seen sucessfull reefs with 1/2lb per g and some with over 2lbs per gallon. __________________ Tom Current Tank Info: Tank of the Month , November 2011 : 600gal integrated system: 3 display tanks (120 g, 90g, 89g),several frag/grow out tanks, macroalgae refugia, cryptic zones. 40+ fish, seahorses, sps,lps,leathers, zoanthidae and non photosynthetic corals.

03/10/2008, 09:09 PM	#4
demonsp Moved On Join Date: Jul 2006 Location: el paso tx Posts: 7,634	2 lbs per gallon to much. 1 lb per gallon is great as you will add more as you add frags. Then if its a new setup then a good mix of base rock and LR is better and less expensive. You want space for water flow and CUC to get all around.

03/10/2008, 09:25 PM	#6
demonsp Moved On Join Date: Jul 2006 Location: el paso tx Posts: 7,634	There are so many varibles and to keep it simple start small. The minimum of 1 lb per gallon for less trouble.The more rock you have the more flow and feeding rutine and maintance are needed.

03/10/2008, 09:39 PM	#8
demonsp Moved On Join Date: Jul 2006 Location: el paso tx Posts: 7,634	My main point is to start with the minimum.If you have trouble then ruleing out the amount of LR would be nice. Get the basics in order and then start adding.