Newb Questions- Substrate, HOB filters, Rock selection, etc

MrFishy

Junior Poster
Mar 24, 2009
3
0
1
Petaluma, CA
Hi all,

I'm starting a new planted tank - 20H, med/low light, low-tech - and had a couple questions. I've been reading non-stop for months now but I'm still having some problems planning out my aquarium. Please excuse the large volume of questions- I'm sure some the answers are in these forums but after searching on most of these topics for hours I'm thinking that perhaps a more efficient way would be to ask you gurus.

1) Substrate- I'm looking to grow a nice carpet of HC (or maybe something easier), using the dry-start method on a black substrate. Basically, I'm wondering how to do my substrate. I've already got a bag of ecocomplete, some sand, gravel, and access to wetland mud.

I was originally thinking of using a layer of old aquarium gravel (it's full of mulm), and then putting the ecocomplete on top.

Substrate being very difficult to change I want to do this right the first time. I'm wondering if I should add peat, mud, or gardening soil. I know there's a lot of possibilities, but in your personal opinion, what do you think might be a good combination?

I'm noticing most people tend to put their ecocomplete / other specialized soil on the bottom. Why is this, and should I do this? If I do put the ecocomplete on the bottom, can you recommend a black or grey substrate to put on the very top that isn't expensive and won't hurt my cories?

Another problem I have with substrate is that the slope I pile the substrate in always eventually slides to become quite level. Anyone have a solution to this? I was thinking of using some kind of dividers beneath the substrate running along the length of the tank, creating a kind of terracing.

2) CO2 -

This might be a stupid question, but I'm thinking of building a DIY venturi external CO2 reactor; can I use a powerhead to pump water out of the tank, through the reactor, then back into the tank? Also, will this kind of reactor work with the DIY CO2 I have?

3) Filtration - I use a HOB filter and was wondering if anyone had any recommendations on how to reduce the surface agitation from this thing. For now, I just put a piece of foam in front of the outlet (this works alright, but it's certainly more vigorous than a canister).

I was even thinking of maybe using a larger Emperor (480? 380?) HOB and then somehow slowing down its pump, to provide more diffusion of the output water.

4) Ph - My well water is quite hard and high in Ph. I'd like to be able to lower the ph from 7.7 to around 7.0 as I'm keeping (and want more) amazonian fish. But I'm having major problems doing that and keeping the KH up (to keep my CO2 levels up). I've tried peat and I've tried some discus buffer but neither of those seem to work.

5) Rocks - I'm looking for rocks but having a hard time testing them- what kind and where can I find the acids people use to test their rocks? The vinegar I use doesn't seem terribly accurate as the only this I can really get it to react with are crushed shells. One of the rocks I've found that altered the pH of my water quite drastically had no visible reaction to the vinegar. Anyways, where can I get this acid?

That's all for now, thanks in advance for any of your help. I'll be setting up the tank soon, maybe I'll put some pictures up too.
 

VaughnH

Lifetime Charter Member
Lifetime Member
Jan 24, 2005
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Sacramento, CA
You can buy swimming pool acid, which is muriatic acid (hydrochloric acid). That is the best I have found for testing rocks. Just be careful with it. Some places that sell acid for spa use have smaller bottles of it, so that would be the best to get, instead of the gallon size sold for swimming pools.

I have never been able to maintain much of a slope in any aquarium substrate, no matter what substrate material I use. I have even tried strips of clear acrylic to build terraces, but the substrate just flowed around the ends to the lowest points. I decided to give up on slopes, but I understand ADA aquasoil is the one substrate material that really will hold a slope.
 

MrFishy

Junior Poster
Mar 24, 2009
3
0
1
Petaluma, CA
Thanks Vaughn, I actually think I have some of that acid around, come to think of it.

Funny I don't really hear much about maintaining that slope everyone builds. Maybe it'd be better for the aquascape not to build it at all.