Bloom of life in my shrimp tank - including hydra!

Tha Bizness

I have a semi-planted red cherry shrimp tank that has just bloomed with life recently. I introduced MTS into that tank and pond/bladder snails hitchhiked a ride on some plants I bought. The population of MTS don't bother me. I actually like them. The bladder snails are another story. The population has EXPLODED and I see egg sacks all over the place (little clear jelly like sacks with dots in them). The RCS population has also exploded and I see baby shrimps everywhere I look. The MTS population has grown but no where near the pond/blatter snail level.

While staring at this tank yesterday I noticed small little brown things on the filter and glass. These are semi fast moving when they do move and are very small dots. I also see what I think are just hatched snails crawling on the glass. These are almost clear dots. I also see a increasing number of nemotodes in the water whipping their way around.

I saw my first hydra in this tank yesterday too. I was kinda expecting them to show up and was excited when I saw it. Very small anchored on a piece of driftwood with his tentacles waving in the current. A few larger shrimp would venture by him and he would quickly either retract or kinda whip out at them. Cool.... I seem to have this huge ecosystem going in this 10 gallon. If I saw all this in my other fish populated tanks I would probably freak out. This tank is my 'lets see what happens' experiment.

For feeding I tend to drop a algae wafer in there daily which the shrimp and snails swarm to. I do weekly water changes but don't vac because I have sand and a lot of baby shrimp. The plants are a couple of large for a 10gal Wisteria plants, a java moss clump and two medium size java fern

I am wondering if I should do anything. I know the hydra can kill and eat baby shrimp. Do they also eat nemotodes? I am also wondering what are the other little critters that are swimming around?

MinaMinaMina

Are the nematodes "planaria"? From overfeeding?

Tha Bizness

That's one of those questions that I see different answers to. In my research I have found where people lump all type of aquarium worms as 'planaria' and them some people separate them into two categories - planaria being the flatworm with the pointy head and two eyes which kinda glide over things in the tank and then the roundworm nemotodes which are much smaller, thinner and do "S" motions in the water.

In both cases they eat detritus so its a sign of too much decaying organics in the water. The bloom of pond/bladder snails point to that as well. I have yet to see planaria (the flatworm) in this tank. I am changing my feeding schedule from 1 daily algae wafer to every other day to cut down on the detritus. I can care less about the snails but I think the shrimp will be good from the naturally occurring algae in the tank for a while.

I'm really wondering what the effect of the hydra in the tank would be and if maybe the 'dots' I'm seeing now are their food source? I can only see one but I assume there are many more. I think they are interesting little creatures but if the primary purpose of the tank is RCS and they may harm them then I would need to kill them off without harming the RCS. The RCS are to small and numerous to move and gravel/sand vacs really are not a option.

I am hoping someone can chime in on the flatworm/roundworm question/debate and the effect of seeing hydra questions.

onemanswarm

Yours sounds like a really fascinating tank! It really is an impressive ecosystem in a 10 gallon aquarium. I'm sorry to say that I don't have anything of substance to add to the discussion, but I'm going to chime in anyway so that it will be easy for me to keep track of this thread. I can't wait to see what the experts have to say! Good luck.

Tha Bizness

It is a very fascinating tank. My others seem boring to this one now with all the non-fish life swimming around. This is the only tank out of 4 without fish. I spend the most time looking it it now.

Yesterday I found a different type of snail. Its not a bladder or MTS. These are more of a circular type of shell instead of a bladder or cone spiral. I saw a few of them climbing around. I guess they reproduce slower and haven't really noticed them before now as they are big enough to spot... I guess they hitchhiked on some plants I bought.

I also found another small hydra. I'm going to get a magnifying glass today and see if I can see any shape to the brownish fast moving specs and search for other life. I wish I had a microscope.

Another question I have is could some of these smallish creatures and worms appear - as in not hitchhiked on a plant or fish but maybe naturally occurring in bodies of water or carried in on dust or something? IDK... just a thought.

To add more info about this tank - At one point I used to have guppies in this tank along with the RCS but moved them out a couple weeks ago. My thoughts are that they and their fry kept this worm and other glass crawling life in check. Now they are gone there are no predators and the population has exploded from that. The guppies where picking off the baby shrimp so they had to get moved. I used to take the guppy fry as snacks for another fish tank so I guess they (the guppies) were thinking a eye for a eye when it came to my RCS...

onemanswarm

The new type of snail you're seeing: could it be ramshorn? Along with pond and MTS, Ramshorn would have a spot on the Mt Rushmore of most commonly introduced snails.

Most likely, I'd guess that all of these unexpected inhabitants arrived on plants or possibly in your substrate. In any event, it seems they appreciate your water parameters!

I did a little poking around and it seems the hydra could be a real threat to small RCS. What's more, they reproduce asexually when food is abundant, so if they do like the RCS (or any other forms of life your tank has to offer), it could get out of hand quickly. On the other hand, some people claimed to have had hydra and RCS simultaneously with seemingly no shrimplet predation.

Among the favorite sources of prey for wild hydra are cyclops and daphnia. I wonder if that might help ID your mystery guest?

Because you've established this as an experimental "see what happens" tank, I'd selfishly prefer if you did just that! I'd love to hear updates as this microcosmic ecosystem continues to unfurl before your eyes. Then again, I'm not the one who invested in RCS!

If you do decide to rid yourself of the hydra, nematodes, and other uninvited guests, check out the spixi snail. This might be a good advocate as they have an appetite for hydra, pond snail egg sacs, etc. but won't go after your shrimplets.

Whatever you do, DO NOT put anything with copper in there!

Tha Bizness

I was wondering if the brown specs where cyclops or daphnia. Those were my first thoughts but they are so small I cannot ID.

I also want to see "what happens" in this little ecosystem. I have read that hydra eat baby RCS but thier numbers are so numerous I think I would have to have hundreds of hydra to make a dent in that population.... Now watch for a post by me in a few months sayng "I have hundreds of hydra! help."

I think I will keep feedings to 1 wafer every other or 3 day and weekly PWC to keep the water quality good. I suspect with all of this life it could get out of hand. On the other hand if one organisms waste is another ones dinner it could keep itself in check as long as some balance is kept.

I am going to check out the spixi snail. Assuming the other critters are cyclops and dapnia I would expect the population of hydra to grow with no predators. I was also thinking a couple of assassin snails to prey on the pond, mts, and now ramshorn snails.. not to many as to clean it completely of these snails but enough to keep populations from exploding. Do you know of any other non-fish predators of hydra?

The initial cost of the shrimp were low so I don't mind loosing them for 'science.' I have been wanting a microscope for awhile - now I have a good reason.

onemanswarm

I've been searching around for additional info on this and although most people regard hydra as a nuisance to be eradicated, I have to admit I'm more than a little envious of your crazy microcosm tank! A few thoughts:

1) As you said, the RCS are prolific breeders so the hydra probably won't decimate the population even if they do acquire a taste for shrimplets. Hopefully, a reliable supply of cyclops/daphnia will draw their focus elsewhere.

2) I never came across anyone complaining of a massive hydra infestation. Many people said that they vanished as quickly as they appeared without any intervention.

3) There are some chemical treatments that will wipe out the hydra or you could jack up your water temp to 100+ until they succomb, but obviously you'd need to quarantine anything you want to keep alive.

4) Any fish that will eat the hydra will probably also relish your shrimp.

5) I read up on the Spixi Snail and I think this is the ideal solution to have in your back pocket. They will eat hydra, they will eat pond snails and their eggs, and they will eat ramshorn snails and their eggs. They cannot eat Malaysian Trumpet Snails. This is ideal because I think you'll want to keep the MTS, especially if you have a sand substrate, and it doesn't sound as if they will completely wipe out the pond/ramshorn snails. Spixi snails also do not reproduce asexually so you can control the population from the start if you can figure out their gender. If not, they will cannibalize young spixis, thus keeping their own numbers in check. Assassin snails will eventually wipe out all of the snails including the MTS and I don't think they cannibalize, so you may end up with a massive population of hungry assassin snails.

6) Bottom line, unless someone with more experience comes along and explains why we're both fools for even considering it, I say let this thing sort itself out! You seem like the kind of person who will enjoy observing the process day to day rather than trying to assert control over it as quickly as possible. And if I'm wrong about you, do me a favor: bag up a bunch of them and ship them my way!

Tha Bizness

Today I found more Hydra. It appears some individuals now have buds growing off of them forming new hydra. They seem to stay in a small localized area still and have only colonized a small area of the simulated driftwood in the tank. It also looks as two individuals have climbed to the end of a strand of java moss and their foot(s) are now combined on it. They just sit at the end of the strand waving in the current.

I saw a smaller sized dead shrimp in the area of the hydra colony. I didn't remove him but the tank took care of his body within a hour or two. It appeared to be eaten by other shrimp and snails.

They are growing in number. I also have seen a huge decrease of the little brown swimming spots.

lorax84

It sounds like you may be overfeeding a bit. I had hydra in my planted 20G last year, they can actually kill baby shrimp so you are probably going to want to control them. Mine disappeared shortly after I moved my Blue Rams to the tank. I'm not sure if the rams ate them, or I just stopped overfeeding at that time.