Coral Feeding

[cookie extreme]

it kills! makes living things sterile so they can't reproduce!

The fact that you nuke a few in the water is completely insignificant, they could just as easily get skimmed anyway.

only a few in the water? isn't that where you want them so your corals feed on them? easily skimmed! hmmn let me see, would be great food source but easily skimmed (then why bother at all with them in the first place?)

by increasing other types by providing more efficient food sources

bugger me must have some smart UV unit if it can tell goodies from badies. and leave still plenty in the water for the corals to eat. wouldn't that mean that your uv is not the working properly if it leaves stuff alive in the water column (isn't that one of the biggest pro's of a UV unit)?

[lduncan]

You suggest not using sand because it takes nutirants away from the water column lowering the amount of food for bacteria and therefore corals, yet use UV which kills those same bacteria anyway? Seems weird to me.

I don't think you guys are thinking. Killing does not equal removing.

It kills some of the bacteria in the water that's all. Corals don't care whether it's dead or alive, to them it's all the same - food.

You also forgot the other part of my statement, which actually says that total bacteria populations were increased, when using UV.

Layton

[lduncan]

it kills! makes living things sterile so they can't reproduce!

So UV is going to kill all the bacteria in your tank?

only a few in the water? isn't that where you want them so your corals feed on them? easily skimmed! hmmn let me see, would be great food source but easily skimmed (then why bother at all with them in the first place?)

You don't need a skimmer for bacteria to be easily skimmed. I don't see your point. Comes to my point before, the more food you have in the water, the more you skimmer will pull out in a certain time. However some people take the fact that the skimmer is pulling a lot of stuff out, as meaning that the water has no food. It's not always the case.

bugger me must have some smart UV unit if it can tell goodies from badies. and leave still plenty in the water for the corals to eat. wouldn't that mean that your uv is not the working properly if it leaves stuff alive in the water column (isn't that one of the biggest pro's of a UV unit)?

UV can only get stuff which is floating in the water. There is a vast amount of bacteria which is NOT floating in the water, like on every surface in the tank.

Whether the bacteria which arrives at corals is dead or alive is irrelevant. It's all food to them.

Layton

[cookie extreme]

lduncan wrote:

Quote:

The fact that you nuke a few in the water is completely insignificant; they could just as easily get skimmed anyway.

only a few in the water? isn't that where you want them so your corals feed on them? easily skimmed! Hmmn let me see, would be great food source but easily skimmed (then why bother at all with them in the first place?)

You don't need a skimmer for bacteria to be easily skimmed. I don't see your point. Comes to my point before, the more food you have in the water, the more you skimmer will pull out in a certain time. However some people take the fact that the skimmer is pulling a lot of stuff out, as meaning that the water has no food. It's not always the case.

that depends again on the skimmer you use (size)

maybe you should open your eyes while reading other peoples posts!

and thats one of my arguments. how good is it to have a very powerful large skimmer? if its so efficient in removing "nutrients" then how much is left for corals? in BB tanks (which are cleaner no disagreement here) the skimmers works more efficient then in a sand bottom tank. so it removes more,

are you disagreeing with that?

I don't think you guys are thinking

temper, hope this wasn't a attack on poor us! :roll:

It kills some of the bacteria in the water that's all. Corals don't care whether it's dead or alive, to them it's all the same - food.

well not to sure on that one. if you change something genetically will it affect the coral (GE comes to mind). also dead stuff tends to break down and wouldn't be as nutritional (unless kept pretty cold)

Bacteria live in broths, they aren't necessarily attracted to inert surfaces because of some need to hold on to something.

BINGO (i know how you like that word )

like our Zeovit rock? produces a nice amount of cloudy stuff daily

[lduncan]

Cookie and suphew, I think there is one thing which is confusing the issue for you.

You are not trying to compare things equally. You are trying to compare your perceptions on the way many people run BB, which is as you say big skimmers to remove as much as possible as fast as possible. To a sand system with less skimming.

There are good reasons why people run BB that way.

However if you're looking to isolate the benifits (if any) of using sand, you have to level the field and have all other variables such as food input, and skimmer output fixed, and look at changing the one variable, the sand, in isolation.

That's were a lot of your arguments fall down. In your reasoning, you're assuming more than one variable changes which is confusing the matter.

Now back to why people run BB the way they do? It's because there is plenty of food available to the types of corals they are keeping, no matter how hard they try to remove nutrients, there is still plenty of food there.

Any BB owner could just as easily let as much crap accumulate in the tank as a sand bed does, but it's completely unecessary. It's totally up to them how clean or dirty they run their tank.

that depends again on the skimmer you use (size)

maybe you should open your eyes while reading other peoples posts!

Skimmer output per unit time is not dependant on the size of skimmer, (except when the skimmer has reached it's absolute maximum limit)

It is dependant on the concentration of simmable material in the water (in this case we'll call it food). Take this for an example. You have two tanks, one with heaps of food in circulation, the other with nothing. Both tanks have a AP902 on them. Which skimmer will pull more out in a hour of running? Clearly it's the one on the tank with the most food in circulation. Now which one has the most food available to corals? Clearly the one with the most in circulation.

So what can you imply from that? A tank with a high skimmer output, is likely to have more food available than one with low skimmer output, all other things being equal.

are you disagreeing with that?

You need to compare apples with apples. Two tanks, one with sand, one without sand, both with AP902's. Which skimmer is more efficient? Answer, they have the same efficiency, as they are the same type and size of skimmer. Then see above. The skimmer which pulls out more stuff implies that there is more food in circulation.

temper, hope this wasn't a attack on poor us! :roll:

Not an attack, it's just that some posts seem a knee jerk reaction. It's just a suggestion to stop to think for a bit. Sometimes it seems that people write stuff without thinking in response to some of my posts, just because it was me that posted it. Just give some things some time to digest, and actually consider what I've said. It actually might make sense.

well not to sure on that one. if you change something genetically will it affect the coral (GE comes to mind). also dead stuff tends to break down and wouldn't be as nutritional (unless kept pretty cold)

Sounds like you've been listening to all that GE propaganda. A lot of people have the wrong idea on what the dangers of GE are. Anyway, how is UV mutation (which incidentally is a natural process) going to effect the corals. They digest this food, which is a process of breaking stuff in order to form the compounds which the coral needs. You right dead stuff does break down. But it doesn't do it spontaneously. There is a class of organisms which cause that break down - bacteria. Also we already know that corals are quite capable of using dissolved nutrients directly, anyway.

BINGO (i know how you like that word )

like our Zeovit rock? produces a nice amount of cloudy stuff daily

Two operative words there 'necessarily' and 'inert'. An inert substance can trap and accumulate detrital matter, which results in large bacterial populations, but you could also have the same amount of detrital matter on it's own, and the bacterial populations would also be there. The sand isn't doing anything special, or necessarily supplying the bacteria with anything in particular.

All the bacteria need are the nutrients. If they can get them in the water, they'll be there, if they can get it living on the rocks they'll be there, if they can get it living on the glass, they'll be there.

I don't really think you want to drag zeovit into this one Lets just say that the rocks are far from inert, and there is more than just bacterial feeding going on.

Layton

[wasp]

Doesn't answer my origional question though.

Why am I seeing better corals in tanks with sand?

[puttputt]

Layton has some good points. wasp, you need to have 2 identical tanks, both with all parameters the same, to really get an answer to your question.

Its turning into an "over skimmed, un fed, nutrient poor BB tank" verses "an under or unskimmed tank with a dsb" argument rather than the original point, which was a discussion on how or if sand in a tank gives better colour.

When we do the tank tours (I'll pm you,like to arrange this weekend if we are all free), you will be able to see some pretty good colours in my tank, with a bb, a 902 skimming well, a calcium reactor, lots of flow, and a sand bed in a refugium. Works for me, as Cookies way works for him and crackers way works for him.

[jetskisteve]

GOOD LORD 9 pages ive only been away 10 days

[TM]

Doesn't answer my origional question though.

Why am I seeing better corals in tanks with sand?

because you live in auckland

[wasp]

Layton has some good points. wasp, you need to have 2 identical tanks, both with all parameters the same, to really get an answer to your question.

I'll agree with that but only in theory. In reality, two identical tanks will not be achieved. You could set up two identical tanks, but I'll guarantee there will be differences. Layton knows that too.

I used to be a BB believer too, and still believe BB is the best way for a clean tank. I'm starting to doubt though that clean is everything. Why? Because what I'm saying is that anecdotally, I'm seeing better corals in tanks with sand. Having been thoroughly brainwashed that this is not possible, it was hard to understand. In fact I still do not understand it. Which is why I am asking for answers.

When we do the tank tours (I'll pm you,like to arrange this weekend if we are all free), you will be able to see some pretty good colours in my tank, with a bb, a 902 skimming well, a calcium reactor, lots of flow, and a sand bed in a refugium. Works for me, as Cookies way works for him and crackers way works for him.

At the moment, I simply do not have the time to pay you a visit. However if you can manage to get over my way you are most welcome it will be great to put a face to the name, and you HAVE to do Craigs also, absolutely healthy corals in a tank with sand.

[reef]

a bb, a 902 skimming well, a calcium reactor, lots of flow, and a sand bed in a refugium

Thats not really BB as you have sand in the refugium. To me BB is no sand anywhere.

[puttputt]

I agree reef, its a bob both ways.

[reef]

I run my tank with sand and attached are two 4ft tanks with BB. The reef looks great and the BB tanks look always dirty. i only clean them once in a while.

I stir my sand once a week which feeds corals. Also noticed that when you stir the sand the tank goes cloudy then it is crystal clear after a day.

No sure why that is the case. Cant do that with a BB tank

Gobies are great for keeping the sand clean.

[puttputt]

seen your set up reef, and I'm sure if it was around the other way i.e. sand in the 4"ers and BB in your reef it would be the same. You wouldn't let your main display tank get dirty regardless if it was Sand or bb. My ref with sand bed is grubby, but thats they way the pods like it

[puttputt]

I think it is same we don't have a functional marine club in Auckland. There is a whole lot of us that I'm sure would enjoy getting together, arranging tank tours, frag swaps etc. I'm sure if we were all talking face to face, we would get to undertsand each other better.

wishful thinking??

[puttputt]

undertsand

fruedian (sp?) slip.

[puttputt]

fair enough wasp, still love to arrange a visit to yours and crackers.

and I'm only 20' from jetskis place so anytime.

[wasp]

wishful thinking??

Shouldn't be.

What's wrong is I put up an idea for discussion, keen to find answers, but the confrontational approach of some turns it into yet another I'm right you're wrong thing, as Caryl said, she was quite right.

Then I get "challenged" to prove this, prove that, the obvious intent being to shoot down everything I say. I'm looking for answers, not claiming to be an expert.

[lduncan]

No one's saying that you can't have a great looking tank with a sand bed.

To me though, sand, when run as a filtration system or for coral feeding, reasons has some major pitfalls. They do eventually lead to negative effects on SPS corals, as well as cyclical algae problems.

To me the critters and bacteria in the sand are nothing more than unecessary bioload. I'm not particularly interested in keeping critters. I'm interested in corals and fish. Some people have other priorities, some people love watching the diversity which comes with nutrients trapped in sand, and that maybe a reason for having sand.

Some don't like the look of BB tanks, so keep a thin layer of sand, which they religiously clean, in order to avoid the long term effects of sand storage. That's another valid reason for having sand.

But to put sand in a tank under the misguided belief that it's going to be more beneficial to your corals I think is wrong.

Some keep things which aren't particularly effected by the longer term effects of the sand, and prefer to deal with them in other ways.

Layton

[lduncan]

Shouldn't be.

What's wrong is I put up an idea for discussion, keen to find answers, but the confrontational approach of some turns it into yet another I'm right you're wrong thing, as Caryl said, she was quite right.

Then I get "challenged" to prove this, prove that, the obvious intent being to shoot down everything I say. I'm looking for answers, not claiming to be an expert.

Your not being challenged to prove anything. Just produce some logical reasoning. True proof is not always easy to find.

Layton

[reef]

I'm sure if it was around the other way i.e. sand in the 4"ers and BB in your reef it would be the same.

I dont have time to clean the main reef everyday. so the sand is very useful as it stays clean.

Yes it does have waste but that is how the nutrient cycle works. you need dirt.

we don't have a functional marine club in Auckland.

Sure we do, just many people dont turn up as they have better things to do.

Next meeting is due shortly.

[lduncan]

I dont have time to clean the main reef everyday. so the sand is very useful as it stays clean.

Yes it does have waste but that is how the nutrient cycle works. you need dirt.

It's not really clean, it's just hiding the dirt from view. And no, you don't need dirt, especially the amounts that accumulate in sand.

Layton

[lduncan]

Doesn't answer my origional question though.

Why am I seeing better corals in tanks with sand?

Are you talking about your tank in particular, or in general?

Layton

[wasp]

But to put sand in a tank under the misguided belief that it's going to be more beneficial to your corals I think is wrong.Layton

That's what I used to think.

The confusion is caused by BB protagonists immediately equating a sand bed with a dirt laden badly managed DSB. I'm not proposing that. I'm thinking sand has pros and cons. If the cons can be managed & nutrient paramenters kept within acceptable limits, maybe it also benefits the tank in certain ways.

To further explain, users of zeovit are meant to "pump" the zeovit rocks daily. When this is done, a cloud of bacterial mulm is released. Shortly thereafter, sps corals can be seen expanding their polyps to catch it. If I get lazy & don't pump them for a few days, corals visibly don't look as good & also go paler. I'm thinking this mulm may be pretty much the same as what can come out of a sandbed.

[wasp]

Your not being challenged to prove anything. Just produce some logical reasoning. Layton

Produce some logical reasoning?

Are you saying myself and others have not done that?

Being polite, all I can say is you must be blind.