getting tired of the battle... would you remove the substrate?

[JackBlasto]

I have had many planted tanks over the past 5 years. One is a discus tank and very deep. 3 feet to be exact. It has about 5-6 inches of substrate that is now pretty old. It is a larger sand like dirt called aquadurt that was for planted tanks ... 5 years now and the plants are struggling. Im guessing the substrate is losing its nutrients. This post isn't for advice on how to correct that. I'm tired of injecting the bed with nutrients (reaching 3 feet every two weeks for 5 years has taken its toll). I'm thinking of pulling all the plants out but worried about the discus health living above a substrate bed like that that has no plants. I know there's some debate on a deep bed like that becoming toxic. Not sure which side I believe as the Discus have been fine for 5 years living above it and the plecos dig it up non stop as well with no noticeable negative health effects that I've noticed but I wonder if the live plants make the substrate bed liveable. Question is, would you siphon out the substrate if you pulled the LIVE plants from the equation?

 

[Delapool]

I'm not sure about deep bed toxicity but would be tempted to remove or lower to something manageable to gravel vacs. This is only from watching the amount of waste that settles on bare bottom tanks.

 

[Fresh2o]

As long as the substrate is not severely disrupted, you could probably leave it as is. However, down the road if parameters start to shift to the negative, you might wonder if the substrate is the cause.
IMO I would remove small portions of it each week or whatever your water change schedule is. Sand should be easy to remove via siphon. That may take some time but it should not present any drastic changes to the water column. Good luck.

 

[Caliban07]

I have had many planted tanks over the past 5 years. One is a discus tank and very deep. 3 feet to be exact. It has about 5-6 inches of substrate that is now pretty old. It is a larger sand like dirt called aquadurt that was for planted tanks ... 5 years now and the plants are struggling. Im guessing the substrate is losing its nutrients. This post isn't for advice on how to correct that. I'm tired of injecting the bed with nutrients (reaching 3 feet every two weeks for 5 years has taken its toll). I'm thinking of pulling all the plants out but worried about the discus health living above a substrate bed like that that has no plants. I know there's some debate on a deep bed like that becoming toxic. Not sure which side I believe as the Discus have been fine for 5 years living above it and the plecos dig it up non stop as well with no noticeable negative health effects that I've noticed but I wonder if the live plants make the substrate bed liveable. Question is, would you siphon out the substrate if you pulled the LIVE plants from the equation?

Healthy plants make for a healthy substrate as they will oxygenate the root area keeping it aerobic.

5 years however is a long time and my bet is that you have quite a colony or microorganisms in that bed. Disrupting it could definitely be problematic for your fish. The substrate may leech ammonia from the detritus that is being broken down.

It can be done be needs to be down carefully. A large bore siphon that is powerful enough to remove it in to a bucket gently would be my method however, a substrate that had been down that long is likely to turn your tank cloudy which may affect visibility.

Leave it down and buy some dry fertilisers for the plants. They don't have to have nutrients at there roots exclusively and will take up through their leaves. Your substrate will have gathered lots of organic matter over 5 years that will retain the nutrients you dose anyway.

I'd leave it be and focus on growing healthy plants or remove the fish and then remove the substrate. I doubt the substrate is the cause of your plant problems. Many people run very healthy planted tanks in inert substrate and whilst dosing the water column. [emoji106]