Added a fun pic of my little 10 gal just because I think she's pretty. Anyways,
As long as I've been keeping fish, I've been under the impression that a water change is especially important in removing buildup of detritus and waste within the tank, as well as chemicals like ammonia or nitrites, which are coming from said waste. I keep seeing people just changing the water though. I always saw these clips of "hands free water changes" and thought, "But if you don't move the siphon through the gravel, you don't remove the source of the issue". But today I saw another one of these videos and thought, "Maybe I'm wrong. Maybe the detritus could be hosting beneficial bacteria as well. Maybe the reason I had such an issue getting my tank to cycle was because I didn't let this dirt lie, and not because of the evil ammonia God."
Have I finally understood some great truth that was obvious to everyone else all along? Should I be leaving the mulm alone? My tank is staying stable with the weekly water changes/gravel vacs I do on it, but I would love to see faster plant growth if possible.
Any new perspectives would be enjoyed!!
Thank you 🙂
Posted by oldmoldylemon
8 Comments
The substrate does hold colonies of beneficial bacteria. It’s only necessary to vacuum if debris is trapped in it and causing issues with keeping your levels in check. IMO
If I’m wrong in anything here feel free to correct.
Almost all fish waste will break down and dissolve in water. Eventually, that waste stops producing nitrates or ammonia and you are left with an area that bacteria can consume or plants can utilize to get any remaining nutrients. If you are overfeeding heavily, that’s a different story.
A spot vacuum when something gets dirty is still totally fine. I stopped vacumming because my microfauna have really taken off combing thigh my gravel. I also only really had shrimondeaths after vacuuming, but I think I was pulling up some of my root tabs.
I never vac the substrate in any of my tanks. I use potting soil with a fine gravel cap.
Here’s my 5gal. Kinda hard to gravel vac. It’s a jungle lol https://ibb.co/DfsbJnDQ
I just let my tanks “do their thing”. Rarely do i do water changes. I closely monitor parameters like nitrate, tds and hardness though
I no longer deep vacuum my gravel. I just agitate the surface and vacuum up the surface mulm. Too many times i released anaerobic pockets of ammonia doing deep vacuums.
[You should be removing mulm by vacuuming when water changing](https://www.2hraquarist.com/blogs/hot-topics/water-change-the-2hr-way?srsltid=AfmBOor2Kc0toA-CjzTQOzGgekRGyzquaeN3JyFmFRW4YcXPd0FqCksA).
I vacuum the surface of the sand. My corys and shrimp get really excited when I disturb the substrate and rush in to see if they can find any food.
Most ammonia comes directly from the fish’s gills. Removing detritus can be helpful if you have bacterial/turbidity issues, but it’s not necessary.
When there aren’t any plants there isn’t much benefit allowing detritus to build up. It will increase the accumulation rate of nitrates. I think it was just a cleaning technique that stuck around just because “that’s the way it was always done”.
Planted tanks have the ability to take up nutrients in the substrate. Walstad’s method involves using food and fish waste to supplement the substrate nutrients.