Phyto and Clams:
In the first post of this thread it was suggested that Phyto be fed to Maxima clams,.. But it is a long held hobby myth that any clam under 3" should be fed Phyto, by means of the boal feeding method, or by putting a container over the clam and injecting phyto into the container,.. or simply feeding it directly to the tank.
There are certainly plenty of phyto supplements out there,.. and it is proven that clams do eat phyto, but do they need it?
Why do we care? Phyto is not something I want to add to my tank,.. it's loaded with phosphate (anyone looked up how they make this stuff?
) and with the exception of some feather dusters and sponges and such almost nothing eats it directly.
Also, phyto is naturally occurring in our tanks,... anyone that has skimmed wet has probably come up with a green skimate,.. that's phyto
at least in part.
The following references are from a book called "Giant Clams in the Sea and the Aquarium" by James Fatherree,.. It's a really good book, and I recommend anyone that's into clams go pick it up. I used to reference a number of different sources for info,.. but now I'm happy to say I don't need to because it's all there.
The book goes into amazing detail at how these numbers were reached, and sites the studies they came from,.. but to avoid copywrite infringement I will just give a brief overview lol.
The first thing the author does is setup an Acronym called "CZARG" (page 45) This is the percentage of a clam's daily respiratory and growth/reproductive needs that are covered by the Zooxanthellae. A CZARG Value of 100% would mean that a clam could satisfy 100% of it's carbon/energy needs by zooxanthellae alone, and not need to filter feed at all to be healthy and grow at a normal rate.
Initially it was thought that the energy provided a clam by the zoox was much lower than it is in actuality so that's where these myths came from, the calculations used to find these first numbers are now considered to be way off.. For details on this I refer you to page 46 and 47.
The book references Klumpp & Lucas (1994) in finding CZARG values (page 48 for below)
2.2cm Derassa (less than 1 inch) =140%
2 cm (less than an inch) Tevoroas = 140%
Refrencing Klumpp & Griffiths (1994) CZARG values
4.2 Cm Gigas (1.68 inch) = 191%
2.4 cm Crocea (just under an inch) = 206%
4.2 cm Squamosa (1.68 inch) = 118%
Page 49
Fitt & Trench (1981) did a study on how Squamosa acquired it's zoox and reported that over a dozen clams were raised from sperm and egg in filtered sea water with no access to particulate foods at all and were maintained for the 10 month study. They didn't do any studies on CZARG, but reported that the clams didn't just live but grew.
Now remember that a CZARG value of 100% means that the clam meats 100% of it's needs for C/E for health and growth/reproduction off just it's zoox and light.
So,.. after reading this data I decided that before I update anything I should probably try this out for myself,... I went out and bought a Maxima clam that was just under an inch,.. but a beautiful blue,.. I'd have been bummed if I killed it. The tank I got it from had Monti eating nudies,.. which forced me to Q this clam for a month under very weak PC lights,.. big mistake. By the end of the month the clam was in seriously bad shape. I moved it into my 125 after the month and immediately left for a week long trip to San Diego (bigger mistake),.. The Clam was then shocked by the sudden increase in light and bleached on me, and to make matters worse got pinched mantle! I was forced to do a FWD on it when I got back from Cali, and I shaded the clam and it slowly started to regain it's color. I then acclimated it carefully to the MH and it really started to take off. It got better and started growing quickly,.. and that clam now 5 months later is almost 3 inches in size.
Do I recommend buying really small clams?
Well,.. They are far more touchy,.. and much more sensitive so I guess it depends on your confidence in your setup and experience with clams,.. but be aware the small ones go downhill much faster than the larger ones will.
I hope this helps despell a hobby myth!
Whiskey