Backyard Aquaponics
A place to discuss aquaponics

I'm not worried about my body image, I stopped worrying about that a long time ago

I've had my little cleaning friends pack up and leave home.

I think the combination of salt and that spell of over 40c degree heat we had for the week may have prompted their departure.

They say that they can survive very high temperatures over 30°C and very low temperatures around 4°C but I can't find any reference to salt, my temperatures never got over 32c degrees so I think salt may have been their downfall.

I did salt up to 3ppt during that week.

That sucks
I have heaps in my tank - over 50 - and have only lost 3 or so over the last year - i think from lack of food.
I generally havent salted my system, although at the start i had it around 2ppt and they were fine.

You needs to eats more spinach!

Ok so whats the purpose of the mussels?? are they for eating of are they contributing to the system??

Generally for acting as a filter for the water rather than consumption, mainly because freshwater mussels are a lot tougher than marine mussels, and because of the likelihood of them storing toxins, etc (though the latter is less of an issue in AP).

Bivalves are filter feeders and because of that will help to keep the water clean, and I think they also help mineralise solids, but I'm not entirely sure on the latter.

Yavimaya I salted up a little over 3ppt but haven't added any food other than what they would have picked up after the fish.

Is there anything other than left over fish food they need?

Were they eaten?

Ron I first thought that might be the case because I found a couple of hard body pieces outside the shells covered in what looked like dust from the clay pebbles, but 3 more not photographed were in the sump and there was no fish in there, and one of those was also outside the shell.

There was a 2 or 3 very small piles of dust from the clay pebbles in the sump and they would position themselves on or beside the dust and eat it, but there was no pebble dust in FT unless it was very fine and couldn't be seen.

So the guys in the sump, maybe lack of food, the guys, the tank, maybe the same?, maybe eaten?, but I never saw any shells that were open enough for the fish too be able to eat, that doesn't say it didn't happen.

There was slight staining on the sump walls from DTPA Chelated Iron and they cleaned that all up, but then that only relates to the guys in the sump, there was no stain in the FT the fish movement would have stopped that occurring.

None of the shells were open more than those in the photos but the body pieces that I found were larger than the shell openings? Maybe they abandon ship when the going gets tough.

My water has been exactly the same, it's been stable for many months with the same readings, 7.2 pH, Ammonia 0, Nitrites 0, Nitrates 0, the only thing that has varied is the salt from 1ppt to just over 3ppt on occasions.

I've spent hours researching before I first put them in the system and and a lot more time since and can't find anything on their feeding habits except that they feed while cleaning the water, so lack of food may have played a part?.

I'd like to replace them, they do a great job in keeping the water crystal clear, but not until I know more about their welfare and diet.

I'm not sure if once they've cleaned the water up their food source has gone?, I thought there would be enough uneaten fish food particles in the system to feed them even in the sum?

As stated above, they are filter feeders.
They will eat fish poo, but mostly they eat the bacteria in the water as far as i know.

I have watched mussels in previous ponds suck up fish poo covered stringy algae and shoot out a perfectly clean ball of stringey algae.

Im sure they dont eat fish food.

they would not have been eaten, I have had to remove mussels from my turtles claws before, a steak knife was needed to open the shell the 1/2mm needed to get the claw out. There is no way fish have eaten them before they died, afterwards, sure. To eat them before death, you would need to crunch through the shell, they are very protective and close at the slightest touch normally.

As for why have them? Because they one of natures "cleaners", even if they are not neccessary, why not have them? they do not do harm and can only be beneficial, even if you cannot see the benefits.

I didn't consider muscles because I figured they would eat the biofilm in my tank which I believe contributes to the nitrification process.

I was just reading through some reports on other species of freshwater mussels, so I'm not entirely sure how the information correlates with your species, but they both suggest that the salinity of the water can impact the health of the mussels, even at lower levels such as yours (2-3ppt).

Basically they suggested that salt at a level of 2-3ppt and higher water temperatures can result in mussel death, or have heath consequences such as reduced metabolism (to a point that they can't recover), reproduction and so on.

Like I said they aren't necessarily the same species as yours so the information may not be relevant, but it may give a clue as to what happened. It doesn't seem like it could be any other poisoning or toxicity because you'd think the fish would be affected too. If anything they'd go first before a mussel I'd have thought.

On the previous occasions you have salted to 3ppt, what were the water temperatures like? What sort of time period in between instances was there? If there is any similarity to what I read, perhaps the increased salting has caused some sort of cumulative affect over time? Maybe they have tolerated it each time but it has been impacting their ability to feed and thrive?

It does seem weird that it's so sudden, and such a shame because they can be so useful!

Yavimaya:

Wow with over 50 in your tank the water would almost be drinkable

In those numbers wouldn't they clean up the water so much as too delete their own food supply?

The fact that you can keep that number without any problems is great and that encourages me to try a few more, if it was the heat that killed them with colder weather coming on I will do my homework and read up and then get some more of the little fellas.

What I need too know is: Will they survive without any other food source other than bacteria and fish poo.

Azira:

Both yourself and Yavimaya are in Victoria and know how hot it got during those 4 consecutive days over 40°C well I recon that's when they would have died. The salinity of the water plus the heat is looking like what happened, there were a few guys lost their Silver Perch during that week and a lot of the worm farms didn't make it either.

Azira I just noticed the sump starting too look a little dirtier than normal and checked on the mussels and found them all dead, it could have happened over a period of time or quite suddenly, because they don't move around a lot it's hard to tell just when they died.


Thanks to everyone you guys are great.

I read that in an aquarium environment they can require food, which seems to be either green algae water or liquid phytoplankton, etc, but I'm not sure how that compares to an AP environment. I'd have thought there would be a constant supply of fish poo/bacteria/etc for them to eat though, without the need for additional feeding?

Mussels move around on a "foot" like snails do.
unlike snails, im 100% sure they cannot eat and move at the same time, they do not have a mouth as such, simply an entry opening and exit opening.
They cannot climb, thier foot is not sticky as such, they might scrape up some biofilm when they move around, however they move ALOT more effectively through substrate rather than solid bottomed objects.
Your fish are the ones who will eat the biofilm, there is also the fact that the small surface area in the tank shouldnt (might do) add much to the process anyway, considering the area of tank vs. area of gravel, so i wouldnt worry


Not sure about the heat, Although maybe you bought the wrong mussels.
There are 2 types - i cant remember the different names, etc - one is flood plain type, the other is river type (?).
I have the flood plain type - bought from aquablue seafoods.
Before i had my tanks setup i had them in a friends pond for a bit, i forget why but his girlfriend pulled them all out and left them on the lawn for about an hour or 2, in close on 40c heat, in full sun - none died.

The guy at aquablue also said my 5k of tank wasnt enough to support them - i bought 100 - They lasted for ages before i moved half to a pond i built in my yard.
I have about 80 goldfish - were very small, now very large - and have run trout in winter too, i cant eplain why only a few have died, but if you start smaller than you did last time, i cant see why the next lot would die.