Switching out Substrate

[101DalmatianMollies]

Hi Folks,

Long time no chat.

I want to do a small overhaul of my tank, as currently it's a bit of a mess (in my view). I still have my 7 corydoras and my 3 lampeye tetras, but feel as if it is underpopulated. I have 2 large, established amazon sword plants, a large piece of driftwood, and a porous rock in there and that's it. I want more plants, especially grasses for the back, as the cory's have laid eggs in the past but all were eaten. The substrate is a small, coarse rock, that I think affects their whiskers, as the majority of my cory's don't have their whiskers anymore.

That being said, I know that just changing out the entire substrate at once is a bad idea. I don't want to shock the tank. Also since the two plants are quite established in the rock, I don't want to disrupt them. I want to move towards sand, and would love some input as to the best way to do this.

My thought is: just to add in sand so it fills all the crevasses between the stones, then over time take out small sections of stone until I remove most of it, and replace it with new sand as I remove the old substrate.

Any and all advice is as always appreciated. Thank you!

[Mike L]

Unfortunately you can't do that.  Like everything in nature the fine will always settle below the course.  In my opinion I would remove half of one side add your Sand. Then when you remove the other half you will just have a transitional  section, mixed to clear out. You can always put the old gravel in a a nylon and leave laying on the substrate as well.

[101DalmatianMollies]

Ok cool! I want to add more plants - is it best that I do that after I've transitioned entirely? Or if I do 1/2, I could plant that half, then plant the other half once I change that? Also, should I leave the stone the amazons are established in?

Thank you!

[Holly]

Personally I'd just swap out all the substrate at once. Use another tank/bucket for a temporary home for your fish. Keep your filter/heater running in the temp tank/bucket, this will allow you to make the changes while keeping the bacteria in your filter alive while your new tank settles. As for the sword plants they are pretty resilient, you don't need to worry about saving all their roots. As long as you keep some they will grow back. Add the new substrate, replant the tank as you would like and if you have a second filter you can run it with filter floss to clear up the water. I've never had it take more than a day to clear. Your bio load is quite small, your established filter should take care of any ammonia the fish produce. Changing out substrate a bit at a time can be very messy.

[Holly]

Oh and don't forget to add your root tabs for the swords before you add water, I forget every time and believe me, it's way easier to do when your tank isn't full!

[101DalmatianMollies]

Oh and don't forget to add your root tabs for the swords before you add water, I forget every time and believe me, it's way easier to do when your tank isn't full!

Like the fertilizer tabs?

I have a 20gal tank in storage that I tested the seals on a while back and they were fine. What you're suggesting is to relocate the 9 fish to the 20gallon and switch out the substrate wholly (it would be easier empty) and then once it settles, return everyone to the 33 gallon? It won't be too stressful on the fish? It'd be possible to do, I just want to make sure I don't lose my fish. Thank you!

[wolfiewill]

I do the same as Holly. If the fish are healthy and have been doing well in the larger tank for a while then there should be no problem. I would also move as much of the plants and logs to the temporary location as well. The fish should be fine. They've been through a lot worse to get to the fish store.

[101DalmatianMollies]

Ok great! Thank you for the advice! I'm glad I have another tank I can use, as that might've been tricky! I'm excited now, I can't wait to get all that substrate out of there!

Now the question is, do I go with white sand, or black? Hmmmm.

[101DalmatianMollies]

What do you guys think if I mixed the two? White sand mixed with black?