how often should i gravel vac?

[JohnsonSBK]

usually i vac my reef tank everytime i do a water change. after the last time i did it, about a month ago i started to see a rise in my ammonia slowly. its been a few weeks and the ammonia has risen to almost 2ppm. my question is since i have apparently vacumed out to much of my nitrifying bacteria how often should i be vacuming? once a month? every 6 month? only when needed?

[BethanyM]

I have never, ever vacuumed my sand in any of my 3 current tanks. All sand beds are 1-3 inches deep. My sand beds are FULL of life and would hate to disturb it.

Right before water changed I blow out all the rocks with a pump or baster and then start siphon.

[Grandreef 2]

Some people never vacume their aquariums but most peolpe are going to tell you to vacume every month or so.

[JohnsonSBK]

ok, perhaps a better question is what is the advantage of vacuming? why would you want to?

[sedor]

If your running a shallow sand bed (under 3") then its not really providing and denitrification and is purely for aesthetic reasons. You could vacuum it as often as you like really without causing any problems. It may actually be better to vacuum more often so as not to build up detrius and cause ammonia problems. You should never ever see ammonia in the tank.

The word vacuum is what is a little confusing. I don't vacuum the sand per say, but more or less just stir it up. Reason being when I use a gravel vac like those meant for freshwater systems it removes to much sand and I end up with an inch of sand in the bottom of the bucket.

[JohnsonSBK]

i figure i have about 2 to 3 inches of sand, it could be that i have miss diagnosed the problem however the only other thing i could think it would be is feeding and i believe i dont feed to much at all if anything underfeed especially lately. and i wouldnt think my tank would be over crowded with 12 small 3 medium fish...

[John Zillmer]

usually i vac my reef tank everytime i do a water change. after the last time i did it, about a month ago i started to see a rise in my ammonia slowly. its been a few weeks and the ammonia has risen to almost 2ppm. my question is since i have apparently vacumed out to much of my nitrifying bacteria how often should i be vacuming? once a month? every 6 month? only when needed?

How often do you do a w/c? How much do you change? How much live rock is in the tank? Is there a skimmer? Is there any other biological filtration? How long has the tank been set up?

All these questions seem relevant since you may be doing too large of w/c too infrequently, or the tank is very new or has insufficient biological filtration.

[JohnsonSBK]

i do a water change once a week @ 20 gallons i have about 120 pounds of LR and i have a asm g4 skimmer

[John Zillmer]

If the tank is new (<3 months) and you already have 15 fish in it, I suspect that the NH3 issue has nothing to do with your w/c habits and is a result of stocking too quickly.

How big is the tank? What kind of fish are they, and what exactly is 'small' and 'medium'?

[bertoni]

2 ppm of ammonia is a serious problem. I'd start doing some large water changes and dose some Amquel, and definitely get a second opinion on the test kit. Some more details on the setup might help. I agree that vacuuming the sand is unlikely to be the problem, but disturbing a sandbed can dump some nutrients into the water column.

[JohnsonSBK]

ok the tank has been set up for 7 months. i consider small fish under 2 inches such as green chromis and medium 4 inches. the type of fish are 5 green chromis (small), 1 four line wrass (small), purple firefish (small), bar goby (small), yellow eye tang (small) anthia (small) and a yellow, purple and clown tang(medium).

when my ammonia first hit 1ppm i did a 35 gallon water change and then had my ammonia pop back up within 5 days when i did a 30 gallon water change the rest have been 20 gallons every 7 days. and i change my carbon every 3 weeks but have moved that to every 2 weeks with chempure elite instead of bulk carbon.

the tank is a mixed reef with 5 acros, 3 monti, 3 hammers, and a brain coral. G4 skimmer, filter sock, 2 vortech mp40, 1200 return pump 1/3 hp chiller. i feed 1 cube of shrimp every night and a small pinch of sprilina/cyclopes mix. before ammonia issue i used selcon once a week but was advised to stop until thi was better.

[John Zillmer]

2PPM NH3 and you still have 5 acros? Have you confirmed the accuracy of the test kit?

I'm stumped, and following along to see (hopefully!) this get figured out.

[JohnsonSBK]

well ive lost my picolopora, it seems to effect my lps more than the sps, but there has been definate polyp ressesion. which is why im trying to figure it out. i added some stress zyme and that cut my ammonia in half today. i mean added it last night just tested it went from 2ppm to 1ppm

[John Zillmer]

i added some stress zyme and that cut my ammonia in half today.

Huh. That implies that there is a lack of biological filtration. I assume all the LR has been in the tank from the initial setup, and that it was in fact all live rock. If not, that might explain what you are experiencing.

[bertoni]

I'd stop all feeding, at this point. How much ammonia shows up in some freshly mixed saltwater?

How big is the tank? 120 lbs of live rock isn't all that much for that many fish.

[JohnsonSBK]

all the LR has been in this tank from the start and was in my last tank for 2 years im pretty sure it is legit. 120 probly is a little under wat i should have for a 150 gallon tank. also i didnt feed them at all for 3 days dont want to go much longer than that i figure if it is a food issue that long should show that to be the problem. ill check wat fresh salt water tests at shortly

[bertoni]

That sounds like a good plan. Given that the fish are fairly small, the tank should be okay, given your description.

[JohnsonSBK]

just tested fresh saltwater with the results showing it between 0 and .25 so obviously my test kit could be better...

[JohnsonSBK]

does anyone know of a good reliable ammonia test kit?

[John Zillmer]

does anyone know of a good reliable ammonia test kit?

I think for our purposes, really any ammonia kit is fine. If it reads zero or thereabouts, then no worries. If it reads anything substantially more than zero, there are major problems that need to be addressed. I don't think that accuracy and precision are really important for ammonia testing in a reef -- just a red light/green light indicator would be fine:)

The upshot here is that the NH3 is not coming in from your source water (which I sure hope is RO or RODI), so the problem and mystery still remain.

[bertoni]

Actually, fresh saltwater often has a trace of ammonia, so the kit might be okay. I've used Salifert and IO kits, and they've been fine, if you want a second opinion.

I'd get some Amquel going while we try to understand this problem. How long have the fish been in the tank?

[sedor]

ok the tank has been set up for 7 months. i consider small fish under 2 inches such as green chromis and medium 4 inches. the type of fish are 5 green chromis (small), 1 four line wrass (small), purple firefish (small), bar goby (small), yellow eye tang (small) anthia (small) and a yellow, purple and clown tang(medium).

How big is this tank? I'm counting 13 fish, 4 of those being tangs! There's your problem right there, even in a 120 that is to much of a bioload. Not to mention the purple and definitely the clown are going to outgrow the tank quickly.

[JohnsonSBK]

its a 150 gallon

[JohnsonSBK]

however, its only 3 tangs now as my clown died a few days ago when the ammonia peaked

[JohnsonSBK]

no new fish for over a month prior to ammonia spike. please bare with me on splitting the posts. my GF tanks sump is leaking and i need to shop for a new one and am trying to see the trading forum... sorry if thats dishonorable.