Substrate change after filter change

[Floyd R Turbo]

To follow up with this thread I started...

http://www.aquariumadvice.com/forums...se-113632.html

...I now want to start a discussion about the next change I want to make in my tank - possibly changing out the substrate to a more plant-friendly type. On this subject, I am completely clueless, and I am asking for a whole bunch of input.

The first thing I plan on doing, once I get my new canister filter, is to leave the UGF in place w/power heads running, install the canister, and fill one tray with gravel to get bio going. I plan on getting the Cascade 1200 which has 4 trays, so I can fill the second tray from the bottom (and maybe just both of them) with gravel, then the top 1 or 2 with bio media, and let it run like this for at least a week or two before shutting off the UGF and pulling the plates. Then I can re-configure the trays in the canister. So that's step #1

Step #2 is where it gets fuzzy. I currently have about 3 inches of plain old gravel above my UGF. I understand that there are several different types of substrate but am uneducated about the benefits and detriments of each kind or style or brand for that matter. So help me out please!!! Give me some benefits/detriments/experiences with everything you know about. Here's a few items to start, based on what little I know:

Gravel size - fine, large?

What about Flourite? Read a little bit about it.

How about crushed coral?

What about sand?

Which is good for plants, is there a kind that is best in general?

Will some plants not grow in specific kinds of substrate?

I plan on packing the tank with plants once the canister is running, right now I have hyper-duplicating Vallisneria, a sword that is struggling (2 actually) and a couple Echinodorus, one is great, the red one is holding it's own. I would like to add as many plants and decor as possible after pulling the plates.

As for the method of changing out the substrate, the first question I have is related to the nitrogen cycle. Having been in the hobby for 20 years on and off, I am very familiar with it. That being said, I've never changed out substrate on an established tank.

If I have enough of a bio colony established in the canister filter (say I let it run for a full 6 weeks) could I theoretically change out all the substrate at once without causing a cycle? Or would it be wiser to do it in stages, say 1/2 the tank then another 1/2 a few weeks later? Or maybe in 1/4's every few weeks?

Any finally...should I even bother? Is the gravel I have just fine? Check out my pics...

Any advice is greatly appreciated!

Thanks

[mgamer20o0]

my guess is you want to do this semi cheap? your best bet would prob be something like turface. its a little harder to find since its not marketed for planted tanks but it does work. its about $25 for 50 pounds. what size tanks is this?

i have switched over the whole substrate but it was planted. you should be able to do it all at once but there is chance of mini cycle.

[Floyd R Turbo]

Originally Posted by mgamer20o0

what size tanks is this?

It's a 55. I'll have to look up Turface.

Your post brings up another question: what depth of substrate is generally good enough for most plants?

I won't be going with particularly hard to grow plants, just the standards you can get about anywhere...

[mgamer20o0]

2-4 inch there other stuff out there like eco or flourite that are made for planted tanks but they tend to run $20 a bag.

[robott]

i've read that if you're going to switch out your substrate, you can put a few handfuls of your old stuff in pouches made from new panty hoes and let those float for a bit.

[Floyd R Turbo]

The bacterial colony forms on every oxygenated surface of the tank, but with a UGF it is mainly formed on the gravel/substrate since the water flows through it. My understanding in this case is that changing all of it at once would cause a significant loss in colony, and just floating a bag of it would help the colony get started, but bacteria need time to multiply, and in a decently stocked tank, I just don't know if that's going to be enough.

My question regarding the cycle is really focused on the canister filter. If I get the colony established in the canister bio-media, will that be strong/large enough to maintain enough ammonia and nitrite consuming bacteria to avoid even a mini-cycle? Perhaps after I go through a few weeks with some gravel in one of the trays to seed the bio-media, I then rotate the newly seeded media one tray down and add yet another tray (or more) of new bio-media, and mix the old/new together, and let that get established?

[krap101]

Best thing you could do is run both filters, and change the substrate, and after a couple weeks you can take out the old filter. I'm not sure on the mini cycle, but most likely it won't be very severe. as long as you have some decent source of bacteria.