Annual substrate "super-cleaning" helpful in planted tank?
 

What are the opinions on doing a really, really, complete gravel vacuum in a planted tank once a year? I'm talking about literally pulling up plants and getting every bit of the substrate vacuumed. I have a planted tank and, since it's planted pretty heavily, I don't do a deep gravel-vac anymore. I'm starting to have more issues with diatoms as the tank ages (probably silicates from my tapwater?), but will silicates build up in the substrate over time?

My ecocomplete substrate is pretty deep in the tank, 3-4" overall and it seems to me that a really good removal of the accumulated "mulm" once in a while might be a really good idea for a closed system like an aquarium!

First, as a disclaimer, you know my tank is well planted with plastic plants in a gravel/sand mix substrate... but...I have been an organic gardener for 30+ years. I've made tons of compost and vermicompost to feed the soil.
So I gotta tell you my friend, I have mixed feelings on this one. Although there may be some benefit in the eventual tear down and start over, I often think some with a planted tank aren't really thinking biotope or organic aqua gardening. Sand and other sterile substrates require a lot of ferts to keep plants going while a more natural condition is to let detritus break down to help feed the plants. (Okay, a really more natural condition would be to have a sand capped soil substrate, but that's another thread.)

Bottom line is that it's up to you. If the plants aren't doing well or there's some water quality issue that can't otherwise be explained or resolved, perhaps a tear down / do over is the answer. Otherwise, I'd welcome the detritus/mulm to feed the substrate and subsequently feed the plants.

(just my $.02 worth)

regards,
AD

Perfectly valid argument, but I'm using CO2 and EI dosing now, with a ton of nutrients added to the tank. Conversely, I'm also "taking out" nutrients in the form of plant trimmings... so perhaps it balances out?

Other opinions out there?

I would agree with AD with respect to natural planted tanks. All this "stuff" you are intending to remove is the sole source of the tank's biological equilibrium, so removing it is in effect tearing down the entire tank's biology.

Moving to a high-tech system, I would have to think some of this must still apply. While the CO2 and major nutrients that natural systems rely on the substrate to produce are here being added artificially, there is still the whole gamut of bacteria, both aerobic and anaerobic, that lives mainly in the substrate, and any sort of major "cleaning" is bound to disrupt this balance significantly. The nitrification and denitrification bacteria are essential to a healthy balanced aquarium, and all this resides chiefly in the substrate.

I never touch my substrates unless I tear the tank down to set it up differently, with a different substrate. I guess the longest I have had a given tank running untouched is five years. I have either moved, or reset the tank for a different aquascape aside from this.

Byron.

Thanks Byron and Abbeysdad. I appreciate the well-reasoned opinions.

Still don't know what I'm going to do about the diatoms, aggravating, but not critical. The problem is on my stem plants, zero issues on the broad-leaf plants but that could be due to the 6 BN plecos in the tank. Thinking about moving some of the plecos to another tank (getting tired of so many holes in my sword leaves) and getting some otos. Might be risky with angelfish in the tank though!

Farlowella vittata would be an ideal fish for diatoms, provided this is soft water. Like otos, they are tireless.

Diatoms in established tanks are mainly due to silicates, whether in the source water, or the substrate composition (silica sand for instance). Low light is also a factor, but that would not likely be so in your case.

I have 3 Otos in my 55 gallon tank with 5 Angels and I have yet to see any problem with the Angles going after the Otos. The Angels are not full grown yet soo it might be a problem later on :-?

Interesting suggestion, nice size fish that never seen offered locally, but never really looked for them either! My water is really soft 1-2dH, so that's not an issue.

I know several people who have otos with angels and have no problems. Might depend on the adult size and temperament of the individual angelfish.

My angels were babys when I introduce them to the tank which the Otos were already in there. So this might be some of it.