I’ve had a 30 gallon densely planted freshwater tank since 2005. Current inhabitants are about 10-15 corydoras (hard to count—they hide!) and until recently some shrimp (they were supposed to be Amanos, but I read somewhere they don’t reproduce in freshwater, and I caught one of them laying eggs, so...). The shrimp died off over the last few months (pretty sure—they hide too, especially when molting, but I usually would see at least one or two at feeding time, and I haven’t seen any for over a month). I’m telling you this because that might have been a canary in the coal mine thing.
The tank has always had plenty of green algae, both the kind you scrape off the glass and the fuzzy stuff (beard algae?) that clings to ornaments and clumps on the gravel, tho lately there isn’t as much. Plants include Java fern (thriving and producing shoots) and Anubias Barteri and a couple others that do OK with low lighting.
My cleaning regimen has been fairly relaxed for years. I do a pretty big (about1/3 of the tank) water change every 6-8 weeks. Water quality has been stable. I haven’t bothered with filter cartridges for years—I just cut that green phosphate sheet to size, and it’s mainly to filter out debris. I use two, 20-gallon biowheelfilters (I figure I might not notice right away if a filter gives out so having two might keep things stable until I catch on). The plants have done most of the work keeping the water condition stable so the filters are mostly for aeration.
There has always been a slight, pleasant algae smell when I pull out the filter media. But lately, coinciding with the shrimp loss and the gradual reduction of the algae, I’ve noticed the smell is getting much stronger and less pleasant. It doesn’t smell like rot. It still smells like algae but kind of sharper, if that makes sense. I took a sample to my aquarium store for a checkup and the water quality is good (the Owners of the store recommended adding carbon, which I’ve done, but I don’t notice that it’s helping the smell). The fish don’t seem to be stressed. I’ve done two big (1/3 tank) water changes in the last week, and while the smell gets a little fainter after, it comes back.
The only other change in the tank was, when I saw the shrimp laying eggs, I went online to learn more about how to make conditions favorable for them. I bought some cholla to give the babies a place to hide and also dropped in a few (3-4) alder cones. I boiled it all for 20 minutes, changed the water (really dark brown) and boiled again briefly before adding to my tank. During the 2nd cleaning I removed it all and the cholla did have the same strong smell—can’t tell whether it absorbed the smell or caused it. I don’t think the cholla was responsible for the decline in algae or shrimp, as I think both were already on the way out when I added it. It MAY be responsible for the smell, though. Seems like i started noticing the stronger smell around the time I added it.
The most maintenance I’ve done with the filters in years is just take the intake tubing and filter media out and rinse them (I replace the media one at a time when they need it). Maybe I should pull the whole filters off and at least rinse them out. I’d been considering switching out for sponge filters—if I do I’d just change one at a time and wait a few weeks to do the other just to prevent the tank from cycling. I think the plants will protect against that but I don’t want to make too many huge changes at once.
Yeah, I know this is long, but I wanted to give as much info as I can. The smell is strong enough that I catch whiffs when I’m walking past the tank now. Something has to be off. Anybody have ideas what it might be? I‘m thinking of doing another water change later today or tomorrow, so if you have any advice I’ll try it when I do that.
Thanks in advance!!
The tank has always had plenty of green algae, both the kind you scrape off the glass and the fuzzy stuff (beard algae?) that clings to ornaments and clumps on the gravel, tho lately there isn’t as much. Plants include Java fern (thriving and producing shoots) and Anubias Barteri and a couple others that do OK with low lighting.
My cleaning regimen has been fairly relaxed for years. I do a pretty big (about1/3 of the tank) water change every 6-8 weeks. Water quality has been stable. I haven’t bothered with filter cartridges for years—I just cut that green phosphate sheet to size, and it’s mainly to filter out debris. I use two, 20-gallon biowheelfilters (I figure I might not notice right away if a filter gives out so having two might keep things stable until I catch on). The plants have done most of the work keeping the water condition stable so the filters are mostly for aeration.
There has always been a slight, pleasant algae smell when I pull out the filter media. But lately, coinciding with the shrimp loss and the gradual reduction of the algae, I’ve noticed the smell is getting much stronger and less pleasant. It doesn’t smell like rot. It still smells like algae but kind of sharper, if that makes sense. I took a sample to my aquarium store for a checkup and the water quality is good (the Owners of the store recommended adding carbon, which I’ve done, but I don’t notice that it’s helping the smell). The fish don’t seem to be stressed. I’ve done two big (1/3 tank) water changes in the last week, and while the smell gets a little fainter after, it comes back.
The only other change in the tank was, when I saw the shrimp laying eggs, I went online to learn more about how to make conditions favorable for them. I bought some cholla to give the babies a place to hide and also dropped in a few (3-4) alder cones. I boiled it all for 20 minutes, changed the water (really dark brown) and boiled again briefly before adding to my tank. During the 2nd cleaning I removed it all and the cholla did have the same strong smell—can’t tell whether it absorbed the smell or caused it. I don’t think the cholla was responsible for the decline in algae or shrimp, as I think both were already on the way out when I added it. It MAY be responsible for the smell, though. Seems like i started noticing the stronger smell around the time I added it.
The most maintenance I’ve done with the filters in years is just take the intake tubing and filter media out and rinse them (I replace the media one at a time when they need it). Maybe I should pull the whole filters off and at least rinse them out. I’d been considering switching out for sponge filters—if I do I’d just change one at a time and wait a few weeks to do the other just to prevent the tank from cycling. I think the plants will protect against that but I don’t want to make too many huge changes at once.
Yeah, I know this is long, but I wanted to give as much info as I can. The smell is strong enough that I catch whiffs when I’m walking past the tank now. Something has to be off. Anybody have ideas what it might be? I‘m thinking of doing another water change later today or tomorrow, so if you have any advice I’ll try it when I do that.
Thanks in advance!!
