View Full Version : What is daphnia?
NJ Devils Fan
08-27-2003, 7:59 PM
Everytime I am at the store getting frozen food, I see daphnia(sp?) made by hikari. What the heck is it?
Matt W
08-27-2003, 8:24 PM
http://ebiomedia.com/gall/classics/Daphnia/daphnia_gen.html
Hebdizzle
08-27-2003, 8:53 PM
I've seen those under a microscope... bloody ugly guys I'll tell ya.
Aaron
BTW I reccomend Hikari freeze dried blood worms. My fish totally devour them! However, I have yet to try any of their other products.
NJ Devils Fan
08-27-2003, 8:59 PM
I am feeding the hikari frozen bloodworms and I am trying the tubifex worms, I hope my fish like the tubifex.
Dangerdoll
08-27-2003, 9:50 PM
NJ, I think I heard somewhere that tubifex wasn't such a desired food unless they are the frozen kind because of the potential of diseases they may carry and transfer to the fish eating them. You are aware of this, right?
anonapersona
08-27-2003, 10:15 PM
I just today tried some frozen daphnia. They are very small. The little tetras that are still in quarantine gobbled them up. Much smaller than brine shrimp, so for very small fish, a good choice.
I've been reading up on how to raise them myself, but I don't know if I have enough fish to make it worth the trouble.
tricksterpup
08-27-2003, 10:26 PM
daphnia are great live foods, i have been told they are like laxative for fish if fed to much. I have actually raised live cultures and feed dehydrated daphnia to my fish.
Daphnia will feed on green water readily. I have containers of very green water go clear within a week.
A great site for culturing them is:
http://www.aquaculturestore.com/info/daphnia.html
you can also order cultures from this site.
Another helpful site is our own wetman's site. (smart man)
http://www.skepticalaquarist.com/
hope this helps, I also prefer these guys over worms as additional feeding supplement. I know what is in these guys.. :)
jim
NJ Devils Fan
08-27-2003, 11:16 PM
DD, they are the frozen kind by hikari along with the bloodworms. So I was thinking, maybe I should feed daphnia on like friday to clean the fish out because saturday is my fasting day. What do you think about that?
Dangerdoll
08-28-2003, 5:17 AM
Frozen is the way to go if that's your purpose NJ. I think it's a great idea to use the daphnia to help the clean out process. ;)
Can daphnia be used to control green water?
tricksterpup
08-28-2003, 9:21 AM
Matak:
I have heard stories of people building refugiums and keeping daphnia in them. I think i saw something like that at the Krib, but don't quote me on that, some time ago. But if you have an empty tank and lots of green water, you could do that and have tons of live food when you need it. :)
jim
wetmanNY
08-28-2003, 10:14 AM
Yes. Absolutely. The problem is that the fish will hunt them down and gobble them up. Some tangles of Java Moss would help. They need a "refugium."
In aquaria with soft acidic water, copepods take the place of daphnia. They aren't as efficient, working as filter-feeding grazers on the green water/cloudy water plankton, though. But smaller critters are also eating greenwater algae, bacteria etc. Rotifers, for instance.
I think a healthy plankton population does more to keep aquarium water clear than any pro-active measures we can take.
Originally posted by wetmanNY
In aquaria with soft acidic water, copepods take the place of daphnia. How about soft neutral water?
Looks like the only way I could keep daphnia in my tank would be to run a sump and keep the critters in the sump. Would it work to keep the daphnia in a fry box or something similar?
If you are using them to improve water quality - i.e., a higher-than-bacterial biofilter - the refugium is exactly the concept. I learned this and adopted it originally from Pet Library's "Advanced Aquarist Guide" by Feroze N. Ghadially, 1969. Long out-of-print, but a quite useful technique to me over the years since.
If you are raising the daphnia for food, a separate tank/container (to retain the green water you will be adding) is better IME. Green water I generate by exposed to the water column pieces of Jobes' plant spikes.
The Hamburg Mattenfilter design looks promising as a refugium. At Tom’s Place http://www.tomgriffin.com there’s a thread in the Aquarium Technology forum and an article in Aquasource about them.
I collect both daphnia and copepods from acidic waters, so if your tank water matches the source it shouldn’t be a problem. What I have noticed is that daphnia populations are stronger during spring/early summer whereas copepods dominate in the late summer/fall. Probably due to the changing plankton composition and predation (fish hatchings, cyclops, insect larvae) throughout the summer.
Tom
Tom.E - let us know if you do use the Mattenfilter as refugium. I considered setting shrimp breeders with them, but backed out and am using existing sponge filters.
NJ Devils Fan
08-28-2003, 11:42 PM
Originally posted by NJ Devils Fan
So I was thinking, maybe I should feed daphnia on like friday to clean the fish out because saturday is my fasting day. What do you think about that?
anyone.....anyone..... bueller.....bueller;) ;)
Originally posted by Dangerdoll
Frozen is the way to go if that's your purpose NJ. I think it's a great idea to use the daphnia to help the clean out process. ;)
NJ Devils Fan
08-29-2003, 9:23 AM
WOW, didn't even see that.
RTR- Probably this winter. I’m very interested in seeing how well the organisms in the upper substrate of a tank colonize a maturing Mattenfilter. To me the mat looks like it has excellent potential as a supplementary feeder in a fry or invertebrate set-up.
As for as a refugium, the tank I plan on aging the mat in already has a few hundred daphnia in it. So there will definitely be some daphnia “trapped” between the mat and glass. :)
Tom
Great, I'll look forward to updates. I am big on sponges for tiny fry and inverts, and since Tetra gave up making the ones I use, I definitely will have to use alternate techniques sooner or later.
anonapersona
09-01-2003, 7:37 PM
Hi Tom E., sorry to eavesdrop but could you explain what you just said? I don't understand what you are talking about but I'll bet it is interesting.
wetmanNY
09-01-2003, 7:49 PM
poor anonapersona! Quite right!
Here's a link to this interesting filtration development: http://www.tomgriffin.com/aquasource/mattenfilter.shtml
If you google "aquarium mattenfilter" or worse "Hamburger mattenfilter" all the discussion-- there's lots and lots-- is in German!
anonapersona
09-01-2003, 10:42 PM
I know that I've read everything posted in the archives there, except maybe the saltwater stuff, and I've never seen that article.... is there some secret decoder ring that I need?
Just continuing OT for a while longer, why is it that an undergravel filter needs to be cleaned but a Mattenfilter doesn't? Is it that gravity takes the fish poo down to the gravel but the chemical wastes are processed by the mattenfilter? Sounds like you'd still have to gravel vac. What if you replaced the gravel with an appropriately pore sized sponge, you get a bigger area, and possibly a chance to bump the tank turnover up a bit without increasing the flow thru rate. There's probably a reason for the to-the-side flow.
Sounds like a neat idea for the goldfish folks, the fancy ones don't do well in too much current and can choke on gravel which they typically browse through. A bare tank is so ugly, this would allow for some attached plants.... I'll send that link to some folks, if you don't mind.
The archives and category lists are months behind, many apologies, hopefully they will be updated soon.