Substrate (Obvious newbie question)

And yet another question:

In a new tank destined to be FOWLR, what amount of substrate is good? I have presently have about 1 to 1-1/2 inches of crushed coral (fairly large-grained) in my cycling tank. I can vacuum the exposed stuff regularly, but I won't be able to reach the substrate that is under the live rock

Related questions:

Is 1-1/2 inches of crushed coral too much? Should I lower it?

Should I remove all the substrate from below the live rock when I place it in the tank?

Thanks.

Yes, to 0. Use live sand. If you don't want to use live sand because of the price, use play sand and seed it with a little bit of live sand. 4 inches is the minimum for a deep sand bed which is recommended for reefs, but I'm sure it would do well in a FOWLR too.

I don't like sand. I have had it in freshwater tanks and it is a pain. I understand there are denitrifying benefits to live sand; however, I will pass on it at this time. I just want to get a fish tank going with some live rock

If I don't do sand, then, how much crushed coral/dolomite should I place in the bottom (with no UGF)? Just enough for athstetics? None under the live rock? Will some of the crushed coral become, in effect, 'live rock', with the same denitrifying capabilities?

-Scott

What do you not like about it? You don't clean it as you would clean crushed coral. You said you 'will pass on it at this time.' It is very difficult to change from CC to a DSB if you decide to do so in the future. Putting a six inch sand bed will cloud your water for days and stress out your fish, which could lead to ich. It's your tank and if you want to use CC, go ahead. I'm just trying to enlighten you on why CC is inferior. : )

Yes, just enough for athstetics. I wouldn't place any under the rock. You wouldn't want the CC to shift and cause a rock or 10 to fall. The crushed coral will become 'live' but won't house the creatures that a DSB would. Also, the denitrifying capabilities don't come from the creatures so much as a lack of oxygen. I think you should research more of the pros and cons of a deep sand bed vs. crushed coral substrate. But, like I said, it's your

It is better to go bare bottom than crushed coral. Crushed coral will never have significant denitrifying capabilities! It will trap food, junk, fish crap... and produce ammonia. Some of produced ammonia will be converted into nitrites and then into nitrates. But, since denitrification happens in anaerobic conditions, it will never be able even to denitrify it's own produced nitrates. If you really don't want sand and bare bottom put CC just to cover the bottom 1/4' to 1/2' and vacuume it regulary (weekly). IMO vacuuming is pain in the ass, but if you like CC so much then...

Mislav

This means that the only way to remove those nitrates will be lots and lots of water changes. Might as well buy a $200 RO/DI unit and get ready to lift some buckets.

Scott

Define 'a lot'. An 17% change every two weeks is not a lot. Even every week is not so bad. And what buckets? A python to remove water and a $5 fill for a 5 gallon water can at the LFS.

Define 'removing nitrates.' Enough water changes to keep them below 10 or 20 ppm is 'removing nitrates' to me.

Actually, I have started out using 'Crystal Sea Marinemix'. It states it has calcium and trace elements. No nitrates or phosphates. Heck, I probably just stepped on somebody's pet peeve just by mentioning a brand name. *GRIN*

I understand. Thank for the sanity input. I watched the same thing happen in the freshwater newsgroups. Guess what? I have a nicely planted 125 gallon tank with no CO2 injection and only 120W of light overhead. Nitrates

the left 1/3 of that tank. Grrr. And imagine paying $80 for a substrate that you have learned to hate! *GRIN*

I already have set the line in my budget. If I didn't have one, I certainly wouldn't be using an old 30 gallon tank for my first saltwater experience. About the only thing I plan to add that I hadn't originally budgetted is a skimmer. And a SeaClone 100 at that. It is less than 1/2 the cost of the hollowed CPR BakPak II (with the needed extra purchase of a pump). I feel the need for the extra water motion that the SeaClone will provide, anyway.

And I'll probably drop my crushed coral down to no more than an 1' in front of the live rock, with little or none under it. Happy, guys? Remember, I consider the term 'nitrate factory' to be a compliment! *GRIN*

Thanks for all the input, guys!

It's your tank. If you are adamant about not having sand, don't do it. CC is more difficult to take care of and not as beneficial to the tank. But it doesn't matter to me. If you don't mind doing water changes in order to remove nitrates, and vacuuming the CC, that's fine. As far as cost goes, a DSB will cost about $25 ($5 for 100 lbs of play sand and $20 for enough live sand to seed it). You could even seed the sand with live rock or someone else's sand, thus eliminating the $20. I don't know how much CC is but I'll be it's more than $5. I'm all about saving money, but it's better to do something right the first time than have to correct your mistakes later. If you are sure you will not decide to go with sand later, go with CC. I only said to get an RO/DI unit because the weekly water changes that you will be doing will add up quickly. I'm just saying that you should keep that as an option, looking at the long run. I don't have one, neither do I have a calcium reactor nor a wavemaker. I probably won't have any of these because of the cost, so I'm not recommending that you get any of these. My points with the DSB are that it is less work and allows for better water chemistry. I have had 0 nitrates since I changed over.

This brings up a good point. With a DSB there are some animals that are not recommended. Such as horseshoe crabs and sandsifting starfish.

CC at my LFS cost $10 for 20 lbs. I bought 2 bags and it was a little more than I needed to put a 2 inch base in my 46 gal bowfront