Do I need Nitrates?

[justletmein]

I'm beginning my research on clams as I'd like to keep a few in my reef. My HQIs will be here this week and I'll be making a purchase in a few months or so. I read a post over in the general board mentioning that clams *need* nitrates. It was off-topic, so I can't find it now, but it made me curious. Do I actually need nitrates for Maximas? If so, what should I shoot to keep the levels at or will the clam down them to 0 for the most part? My nitrates are always 0, so how the heck am I gonna get some nitrates in my system? lol...

EDIT: goofy spelling error.

 

[firechild]

Yes, clams need nitrates...in fact at clam farms they dose sodium nitrate to keep the levels up. However, I don't know of any reefer that actively keeps nitrate levels up in order to keep clams. Photosynthetic corals also need nitrates but the amount in the tank is enough to keep them going. The nitrates are used by the Symbiodinium spp. in both corals and clams and therefore the algae is removed from the water by the host in much the same way free living algae do.
So basically, don't worry about nitrate levels, some say around 3-5ppm is good for clams but this will only fuel pest algal growth so just stick to what you would do without clams.

 

[Mad Scientist]

Clams in tanks with zero or very low nitrate levels tend to grow very slow (or slower) and do not do as well overall as clam housed in tanks with nitrate readings around 5-10ppm. Many people with clam dominated reefs keep a slighly higher fish level to suppy their clams with nitrate.

Also, another great source of nitrogen for your clams is live phytoplanton, in the wild they cosume tons of it. Heavy feeding with DTs is essential, IMO, for clams keep in ultra clean SPS type tanks. I add over a cup of homemade greenwater to my 29gal every day, my clams love it!

HTH

 

[pistonfister]

So since the clams use up nitrates would you say they are benificail to the fish in the tank by keeping the nitrates down?

 

[justletmein]

That was my next question Piston. Will the clams just suck up the Nitrates and always keep them at 0? If so, I may really need to overload the tank with fish to get it up to 5-10. I'd obviously have to get rid of my caulerpa in the 'fuge. How much Nitrate will a single clam use from a 125 gallon?

On the DT's, one cup a day per 29 gallon?!? I'm going to need to learn to culture this stuff myself as I don't have enough money to purchase for my 125! Off to do more research I guess...

 

[firechild]

So since the clams use up nitrates would you say they are benificail to the fish in the tank by keeping the nitrates down?

In a word, yes, but they are way less effective than free living algae.

Mad Scientist, I disagree that clams in reefs with zero nitrates are very slow growers. I have 4 in my 80G SPS tank and 1 of the squamosas has grown from 3-6" in slightly over a year. All 4 have shown good growth in a similar period.

 

[Squidman]

I agree with firechild. Having a nitrate reading of 5-10 ppm simply means your system has more nitrates than the clams and other bacteria can consume. There's no benefit in that. Ideally you would have just a trace reading of nitrates so you knew there was enough but no more to contribute to the growth of undesireable algae's. If you have absolutely 0 nitrates then the clams may be defficient but you can't have 0 even if your test kit says it. The nitrogen cycle will always produce some amount of nitrates no matter what. Your clams just have to compete for it unless you have enough to maintain a reading just above 0 which means that all nitrate processing organism's are getting their fill.

 

[Mad Scientist]

Well everyone is entitled to their own view, from my personal experiences with clams, I tend to agree with experts like Daniel Knoop and professional clam farms who feel that clams do best in the presence of nitrate.

If you are testing and reading zero nitrate, any nitrate produced by your system (from your fish) is being conveted to N2 by bactetria in your LR/LS or pulled out by maco algae. You clams don't have acess to this nitrogen.

In the wild, phytoplankton supplies clams with nitrogen and depending on the speices and age of the clam may account for 10-80% of the clam's energy requirments. You may be able to get "fast" grwoth without phyto, but, you'd get faster growth with feedings.

Bottom line, IMO, the future of clam keeping is going to be one of more feeding, not less. Check out Jim's thread about a clam which lived for months on no light and just DTs.

Also, for a large tank, like a 125gal, with a single clam, the clam would be target fed either by removing the clam and placeing it in a bowl with DTs or by placing a cut off soda bottle over the clam and target feeding it DTs.

Sure, people keep clams in tank with no nitrate and don't feed DTs, but, you'll also find people keeping SPS under PCs. These are the exceptions to the rule.

 

[firechild]

Also, for a large tank, like a 125gal, with a single clam, the clam would be target fed either by removing the clam and placeing it in a bowl with DTs or by placing a cut off soda bottle over the clam and target feeding it DTs.

Daniel Knop specifically recommends against this in his book. Reason being, clams are not designed to take large quantities of food at a time and therefore the food clumps in their mouth and they "cough" it back out. This means that target feeding results in less food being taken in by the clam than if it were in a tank with a small quantity of phyto.

If you are testing and reading zero nitrate, any nitrate produced by your system (from your fish) is being conveted to N2 by bactetria in your LR/LS or pulled out by maco algae. You clams don't have acess to this nitrogen.

Why would you say this? If the nitrate is free in the water for algae to take in, why is it not available for the clams? As I previously mentioned, corals have the same need for nitrates as clams in order to supply it to their zooxanthellae which have been shown are the same genus of dinoflagellates in both clams and corals. If clams need nitrates in the water, then so do corals and people have had success keeping nitrates at zero with both clams and corals.

 

[justletmein]

Hmmm... Thanks for the info guys. Sounds like a good debate.

So target feeding may be bad due to the clam basically choking.

How about the soda bottle thing with just a little bit of phyto at a time?
Would this be done at night/day or does it matter?
How much would be a good amount to target feed, say DT's?
How much would be good to feed the whole 125g tank?

TIA

 

[anathema]

Why are people so against dosing the entire tank with phyto?

Phytoplankton is food for an immense range of animals, and as long as you don't go from not dosing to dosing 2 liter bottles the next day, populations of animals that need phyto plankton will increase.

Tiny clams on your live rock, small fan worms, cope/amphipods, some soft corals, sponges, tunicates and more all benefit dramatically from phyto dosing and even nitrates to eat. Did you ever wonder why some people's rock looks like bare rock with purple coraline and some other people's rock has tons of little animals? The best rock I ever got was out of some guy's skimmerless eel tank with consistently crappy water. There were so many fan worms/tunicates/sponges on it it was amazing and the rock was 2 years old. Those same animals are what I hold responsible for the stability my nano has with just one large chunk of this rock.

Phytoplankton is a good replacement for food these animals would get in the wild. Even the Tahitian Blend I dose doesn't cause any problems at 10X the recommended dosage. My tank has 0 nitrates. The water turns green for about an hour, and then all the phyto is gone, and it's clear again.

Just my $.02

Gusty

*Edit* I know dosing all at once isn't best, and that I should drip it in constantly, but i tried that and it's a lot more work... I am lazy.

 

[pistonfister]

anathema, How much phyto are dosing that it makes the water green? I also dose it but I only use what the instructions say and it never is enough to change the color of my water.

 

[anathema]

I dose about 5 drops.

I dose about 5 drops.

for a 55 gallon with 20 gallon sump. Tahitian blend is really concentrated. With 5 or so drops you can se a green tint in the water.

2 drops in my 5.5 nano will really turn the water green.

Sometimes I get overzealous and just squirt some in the sump. My nitrates are consistently 0, I think it's beneficial. JMO.

 

[ReefEze]

dup post.

 

[ReefEze]

I add over a cup of homemade greenwater to my 29gal every day, my clams love it!

:eek1:

How do you culture it? Im thinking of starting... that'd be about 2 1/2 cups for my tank a day!!!




RE

ps I do agree that phytoplankton is a "missing link" in our tanks though...I think everything benifits from it.

 

[ReefEze]

Oh, yeah. I would feed at night, but I dont think it really matters.

IMO