just how much ben bacteria lives in the substrate?

BettaFishMommy

BettaFishMommy

finkids make me happy :-)
Mar 17, 2008
5,354
2
62
Deadmonton, lol, Canada
Real Name
Sherry N.
on another forum i belong to, i posted about how i went bare bottom with the big guys' tank, and mentioned that the amount of ben. bacteria lost when i took out the sand was negligible compared to the amount living in the filter media.

another member mentioned that my ben. bacteria took a big hit by removing the sand. i disagree.

this tank is a 55 gallon, running a rena xp2 and xp4 on it. both filters have the maximum amount of sponge and ceramic biomedia (biomax) that i can fit into each filter without compromising filter flow or performance. they are both topped with polyester batting. sand was not even an inch deep before i removed it from the tank.

i hypothesized that i removed very little of the bacteria with the sand. perhaps 15 to 20% was removed (rough estimate). my ammonia and nitrite tests since the sand removal have all come back a definite zero at all times (testing twice a day just to be sure). i did not do any filter maintenance the day i took the sand out, but did do a very large water change (at least 75%, maybe a bit more), and used Prime at approx double dose plus a titch (holy chloramines here batman!). my testing kit is API (liquid regent kit) and it is not expired.



your thoughts on whether the sand removal caused harm to my bacteria or not?
 
i wouldn't have called the amount of sand i had in there 'substantial', as it would have been less than or just under an inch when spread out evenly. as you can see in my avatar, the sand didn't even go over the bottom edge of the tank trim.

it was plain ol' quickrete brand play sand, and was stirred up and pushed around well each water change, approx every 12 to 14 days on average.

part of the discussion on the other forum was that the sand had a larger surface area than that of the filters' media. i know that ceramic biomedia has a TON of surface area on it (most of mine is the type with holes through the middle of the pieces), and sponge has an incredible surface area compared to the actual volume the sponge takes up.
 
I agree, something porous like ceramic noodles are fantastic biomedia. Also consider the fact that the amount of water flow to that media is significantly higher than it is to something like the substrate. More flow= more food/o2
 
jetajockey said:
Also consider the fact that the amount of water flow to that media is significantly higher than it is to something like the substrate. More flow= more food/o2
Click to expand...

that is exactly one of the thoughts that was going through my head, but i just couldn't find the right wording, lol. (note to self, make coffee and wake the grey matter in the noggin up)

the flow in the tank itself is quite good (spray bar on the xp4 and jet nozzle on the xp2, configured so the jet nozzle output crosses over the spray bar output and creates two separate gentle 'vortexes' in the tank, resulting in just about all gunk going into the filter intakes), but i don't think the amount of O2 goodness flowing past the sand is anywhere near what is flowing through the filter.
 
I'm thinking that substrate has the potential to be good media since undergravel filters do rely on gravel, but when you hook up canister filters with commercial media, the BB has more than enough space to colonize. Growth is probably optimized there because they constantly have a food source from all the water passing through the canister, while growth in the substrate is minimized because the BB in the canister hogs the food source. I think going barebottom is fine.
 
I'd be interested to see some reputable sources on this question.
But really, if you have enough space to accommodate enough bacteria to break down all the waste, then you're fine.
If you lose some bacteria when removing substrate, the system should bounce back fine if there's room for more bacteria in the filters.
Bacteria are limited by their food source, not just space, so more space/media doesn't necessarily mean more bacteria and better biological filtration.
 
Although never have experienced mini cycled in any of my tanks when substrates were disturbed/removed, but heard enough mishaps when tanks went thru so called mini-cycle from local hobbyists (usuallynewbies) as well as on many forums.

Dont know exactly why some did have problems as I wasnt there and each individual may do such differently under different conditions. Therefore, would not just accept as proof that such removal of well established substrate wont cause problems/mini-cycle.

Should always monitor before & after (perhaps daily testing for a week) such drastic changes/disturbances just to ensure the safety of fish involved, imho.
 
I think it's often stirred up stuff from the substrate that really causes trouble. Plus by using 2 filters, you have lots of surface area for both bacteria & to catch particulates before the bacteria can be gunked up by them. The large water change probably helped quite a bit too.

Good job with all the testing, I think in my most paranoid mode I've only done daily checks
 
You must log in or register to reply here.
AquariaCentral.com
Top Bottom