Eggcrate/styrofoam beneath gravel/substrate

[truckpoetry]

Hi everyone,

I am about to start rescaping my 125g African mbuna tank - adding lots of Texas Holey Rock and possibly some flagstone slate blocks. BUT, I am a little concerned about digging, etc. undermining rock structures. I read quite a few interesting things about putting eggcrate or foam underneath the gravel or substrate to prevent direct contact - I am also a little concerned about a rock falling against the side. Might just have to stack center-wise to avoid that...

But my primary question is: What type of eggcrate/foam is SAFE to use in the aquarium and where do I go about finding it? Wouldn't want to introduce any nasty plasticy chemicals in there.

Also, if I pick up flagstone from a local lumberyard/stoneyard, any special treatments I should be doing to prevent it from hurting my fishies?

And if anyone else has tips/pointers, etc. for me, I would truly truly appreciate it. I want this to be a nice looking aquarium, but not at the expense of my fish or my aquarium's strength/durability.

Appreciated,
Cameron

[davoz]

I've used eggcrate that was purchased at the Depot $8.

[truckpoetry]

So are we talking like soft foam eggcrate? Like you would put on your bed to sleep on? Or hard foam eggcrate, like actually used in egg cartons?

Help needed.

Also, I am trying to cut my cost a little on rocks to afford a few more fish in this little upgrade...so I am thinking of looking for some "found" rock - i.e. pulled from creek beds, fields, etc. Any ideas on this? Any rocks (aside from those containing obvious minerals) to avoid? I've got a small pile of Texas Holey Rock that's going in there in one area - limestone - which will help me maintain the PH a bit, but also looking to stack some somewhat flat rock like flagstone, sandstone, etc. - any suggestions on what to avoid, and how to tell if it is OK to put in my aquarium? I've seen posts mention a drop of vinegar to see if it bubbles, but not sure what that's testing for.

Anyway, ALL suggestions welcome indeed.

Thanks,
Cameron

[SGypsyMermaid]

"So are we talking like soft foam eggcrate? Like you would put on your bed to sleep on? Or hard foam eggcrate, like actually used in egg cartons?"

neither...it's that hard plastic stuff that you find in fluorescent light fixtures. kevin/structure guy has a pic of it on his site.

[truckpoetry]

GOTCHA...Thanks for the clarification. See, I am always glad to stop by here before doing anything to my tank... now - any suggestions on the rocks? Looking to build quite a bit of structure in there if possible...

Thanks again,
Cameron

[SGypsyMermaid]

i'll let someone else advise you on the rocks, i , personally think that found rocks are too risky, but others disagree. the flagstone should be fine so long as it has not been exposed to any chemicals.

[tom]

Originally posted by truckpoetry
So are we talking like soft foam eggcrate? Like you would put on your bed to sleep on? Or hard foam eggcrate, like actually used in egg cartons?

Help needed.

Also, I am trying to cut my cost a little on rocks to afford a few more fish in this little upgrade...so I am thinking of looking for some "found" rock - i.e. pulled from creek beds, fields, etc. Any ideas on this?

Smooth stones pulled from creek/river beds are generally excellent choices for aquarium use--not only because they're (usually) inert but also because they're safer for your fish to swim around. As for rocks just lying about in a field...I'm with SGyspsy: I wouldn't use them in general.



I've seen posts mention a drop of vinegar to see if it bubbles, but not sure what that's testing for.


People who do this are looking for a reaction between an acid (vinegar in this case) and a potentially chemical-leaching rock. If you drop a a bit of vinegar on your limestone, for example, you will see it fizz as the CO2 is released. This doesn't mean limestone (a carbonate rock) is bad for your tank, of course, only that it will affect water chemistry. By contrast, inert rocks such as petrified wood and lava will have no such effect.

[truckpoetry]

Thanks a lot for the help. I'm going to be putting a good several chunks of limestone (Texas Holey Rock) in which should help me buffer the pH, and then use what I need to get it at around 8.0.

I think there's a creek bed around here somewhere (across the street I believe), so I will probably go searching for some bigger flat stones from there - trying to get a "layered" stacked rock look on one end (with lots of holes and caves).

One last question on this front...How should I "pretreat" these creek/riverbed found rocks before dropping them in the aquarium? I have heard that I should bake them - any specific instructions on this? what temp, etc. I also have heard to use a pressure washer, similar to those at self-service car washes to make sure I get all the grime off, etc.

Thanks SO MUCH in advance (this forum is great!)
Cameron

P.S. thanks also for explaining the vinegar thing - makes lots of sense now...

:dance: my two other batches of Texas Holey Rock appeared today!!! :dance:

[tom]

Hi. Probably the safest way to prepare your rocks for the tank is to simply boil them for a few minutes. (I've used chlorine bleach/water to clean rocks, then rinsed the heck out of em and let them soak in a neutralizing bath, but boiling is what I'd advise.)

[truckpoetry]

Thanks - I shall try that where I can...but some of my rocks are MUCH TOO LARGE to boil? Any thoughts there?

As I drag this thread MUCH longer than it should be...

Cameron

[tom]

You can always use the chlorine bleach solution: Add one part bleach to every ten parts water and soak until visibly clean and then some (I've read on at least one aquaria site to soak for several days. I have no idea where they get their bleach, but anything beyond even a few hours is overkill). Rinse (a lot) until you can no longer smell any bleach at all, then soak in a generous anti-chlorine solution (the same stuff you ordinarily use when doing water changes). Let dry--in the sun, preferably--and leave out as long as possible (now, here we can talk days), although I've added rocks without harm right after the anti-chlorine soak.

Wise to wear eye protection and rubber gloves when handling bleach: Accidents can happen.

One last caveat: While it'd be rare to find a smoothed river stone with metal in it, if you note even a hint of ore, don't use the rock.