55 Gallon Overstocked?

[Ab235g]

Hello all and thanks in advance for any helpful comments.

Just wanted to start out by saying I'm still fairly new I have only had my tank for about 7 months and had it stocked for 6.
I try to maintain good water quality but fear that I can't seem to keep it stable. I had not lost a single fish until this weekend I lost a 3" clown loach a 4" bristlenose and 1.5" cory cat. I do a 30% water change every 2 weeks on friday (lost the fish on sat and sun)and I do a water test after each change.

Things I think could be the cause:

1. Overstocked?
3x spotted cory's (was 4)
1x common pleco (about 3" and already have a new home in place for once he gets too large)
1x bristlenose pleco (died)
1x rainbow shark
5x guppies
5x cherry barbs
5x black tetras
2x dojo loachs (my favorite)
1x clown loach (died was only 3" and like the pleco already had a home for him once he got too big)
1x 4" angel
I have 95 gallons worth of filtration on tank( 1 canister and 1 hang on back)

2. high PH
when tank was initially setup the water from the tap tested at 7.8 and has been there ever since with this last water change it was 8.8 since I hadn't added any new decorations i tested the tap and sure enough It tests at 8.8. went out got some "PH down" and am gradually lowering back down by .2 per day.

3.high nitrate levels
When I did this last water change I also did a pretty thorough cleaning of my sand and stirred it up abunch and even after my 30% water change it tested at 160ppm. quickly did 2 more 30% water changes and it is down to about 20ppm. ( I think i stirred up some nitrate pockets in the sand)

Any thought as to what of those would have killed that combination of fish?
Any tips or tricks to get my levels to be more stable across water changes?

since I hadn't lost any fish up to this point, I am more upset about this than I probably should be.
Thanks again for any information given?

 

[Turbosaurus]

Hey Ab,

Do you have tap water or well?
160ppm nitrate is off the charts, its a miracle anyone is alive, so I want to focus on crisis control before we talk abut stocking etc. To give you an idea, If you did another 30% water change after that reading you're still at 116 before you feed a single thing... and you want them to be under 20. You're still WAY WAY high, like 10x too high. You need to fast the tank, no food for at least 5 days. Water changes 30% as often as you can (2x a day if possible), but before you do, if you've had flash floods or well water at your location, test your tap water first- make sure that's not a source- its really really uncommon, probably not the problem, but better to know for sure. In the long run, up your water changes and test more regularly. Until you get nitrates back under 20ppm, feed them sparingly and only every second or third day until you get to something more reasonable.

Don't mess with the pH up/down chemicals. Going up causes less shock then accidentally bringing it down too far with chemicals. the 30% w/c with 8.8 won't hurt anything and you're buffering capacity will be pretty high- you have a lot of leeway. Just do your water changes and the fish will adjust. All of your fish are really flexible and will tolerate a wide rage of pH. The # is practically irrelevant as long as its relatively stable. Its rapid changes that the fish can't tolerate.

For the long term, You could be overstocked- but more importantly you're almost definitely overfeeding, and maybe not as diligent as you would like to be with your water changes ( I'm the worst!, I didn't realize how bad I was until I bought a dry erase marker to make a note of the next due date on the side on my tank- kinda like the oil change sticker they put on your car window.. Turns out I was going WAY longer than I though.) Just remember, nitrates come from metabolic waste (feeding) and rotting organics (overfeeding and dead stuff)- period. When you hear hoof beats its probably horses, don't look for zebras.

The only way to get rid of nitrates is to remove them (water changes- a lot more than you're doing, if in less than 7 months of nitrate production you went from 0 to 160 with regular water changes.) The only other way to reduce nitrate is plants. You might want to consider some easy to grow plants. They will use some nitrate, especially floaters, DON"T BUY DUCKWEED, you'll never get rid of it, but things like frogbit or water lettuce are a nutrient sink for nitrates and easy to toss when they multiply. You can also try things like hornwart, java moss, even slow growers like swords or anubias (they stay neater, but grow slower - thereby using less nitrate) if you don't have specialty lighting. They're not gonna fix it, but they'll give you a wider margin of error.

 

[WailuaBoy]

Remove nitrates by adding plants. Nitrate can also be neutralized chemically....

 

[Ab235g]

Thanks for the advice I don't have any live plants currently cause i didn't want the additional maintenance straight out the gate but looks like its time to start. and I know the nitrates are not coming from the tap (I am on city water but that is definitely where the PH is from) . as far as the high nitrates I had it down to 20 immediately the day that I lost the first fish. But I have a pretty think layer of sand on bottom and read that nitrates can build up under the sand and get released when it gets stirred. Is there any truth to that? If so , that is probably where the nitrates came from.
Thoughts?

 

[jpierce3]

Hello Ab,

I try to maintain good water quality but fear that I can't seem to keep it stable. I had not lost a single fish until this weekend I lost a 3" clown loach a 4" bristlenose and 1.5" cory cat. I do a 30% water change every 2 weeks on friday (lost the fish on sat and sun)and I do a water test after each change.

Did you use a dechlorinator product when you did the water change?

1. What size tank is this? You mention you have "95 gallons worth of filtration" but do you know the names of the filters or the gallons/hour rate for them?

2. I would not try lowering your ph with chemicals. Generally it does not work and could just make things unstable which is worse. The only reliable way that I know to get ph down is to filter the water through Reverse Osmosis and then add minerals back into the water (expensive and tedious). You may want to test the tap water before water changes if you suspect that it is changing from week to week. Though let the water rest for about an hour before testing incase there is any dissolved CO2 which can mess with the pH test.

3. I like to suggest for any beginner to do weekly water changes. You will test the water before and after every water change for a year. You will know exactly what is going on with your tank. If you are having trouble maintaining a good NO2 level then you can either add in another day or do a larger percentage per week. A once a week routine is much easier to follow than an every other or whatever. And if you skip a week by mistake, it isn't so detrimental.

You mention that you have a "think layer of sand." Did you mean thin or thick? and how thin/thick is it? Is the sand neutral or will it help buffer the ph?

I've never heard of pockets of nitrate in sand. I've had 3-6" Aragonite sand beds on my tanks for years without any problems.

 

[Ab235g]

sorry about the the typo I have what I consider a thick layer of sand about 1.5" and for the filters I have a 700gph cascade canister filter made by penn plax and some random HOB filter that was passed down to me from a friend that says 30 gallons on it.( not sure about manufacturer a marineland size B dissposable filter fits it nice ly and I have some coarse bio foam in it ( kind of pieced it together and plan on replacing soon with a home made moving bed filter using biohome media) all of that on a 55 gallon tank.

 

[jpierce3]

Looks like you might have a Cascade 700 Canister which has a flow rate of 185gph plus the "30 gallon" HOB, you probably have at least 200gph. That means a 55g tank will turn over about four times an hour. That's not bad. You usually want 3-10 times per hour depending on the type of fish and how stocked the tank is.

So I don't think you are necessarily overstocked. Stocked to the point of doing at least weekly water changes. Yes live plants will help some and look good, but I'm not sure if Dojo Loaches will just up root them (don't they like going under the sand?). I've never kept them so I can't tell you for sure.

You might just have some compatibility issues. Some of the fish get bigger and hope they won't eat some of the small fish. I would suggest doing more research and more water changes.

 

[SnakeIce]

The fish could have died due to a combination of the events. Fish don't read ph, they deal with osmotic pressure. More dissolved stuff in the water means a different rate of osmosis to deal with. So over time with your bi weekly water changes the total dissolved solids (tds) in your tank has crept up. Most of the fish had adjusted but the weakest ones as you experienced failed to deal with the increased waste byproducts, which nitrates stand in for since you can test for that one. Or it is possible they adjusted ok, but that adjustment meant they were weakened and something else that happened to be in your water finished them off.

Now the catch is by rapidly reducing the tds of the tank as measured by the preferred proxy, Nitrates, you could have stressed the fish by the quick change the other direction. It could well have been better to bring the nitrate levels down over the week following your discovery that they were that high. And that begins with small changes the first day and doubled each day until you reach 50% water changes. That would have brought the tds down slower to be less stress on the ability of the fish to adjust.

ph down only adds to the tds, so if nitrate (think tds) is high because of lack of sufficient water changes the ph down only makes it higher. You need to make the stuff in the water more dilute not more concentrated by adding something.

 

[Tifftastic]

Are you using strips or a liquid test kit? I'm concerned because you said you tested nitrates at 160 and did 2 consecutive 30% changes immediately and had nitrates read 20 ppm. The math doesn't work.

160 - (160*0.3) = 112 ppm (After first water change)
112 - (112*0.3) = 78.4 ppm (After second water change)

Somewhere along the lines your results got messed up, either that or your changes were bigger than 30%. Even two 50% changes would have resulted in 40 ppm of nitrates. The strips are really not accurate and the liquid is much better.

My other concern is that high nitrates are usually associated with a drop in pH, not an increase. To me this calls into question the validity of your tests.

 

[SnakeIce]

Tifftastic Well, the ph would only drop if the buffering was used up. If the tap is the ph he indicated and did go up from the one value to the second the buffering is likely high enough not to be used up with the amount of water he has changed over time. It may have eaten into the buffering but not enough for the drop in ph to show up yet. Ph crash due to using up the kh is more of a problem with more neutral ph water with less buffering capacity to begin with. His is high enough not to have that problem, mostly because he has changed some water regularly. If he hadn't done any changes there would be the ph crash you expected.

Unless he has calibrated his nitrate test the results are bound to be skewed anyway, so take the numbers as being approximate. You can't expect math to work when the values have as potentially great a +or- as a hobby test can have. It does help point out that the values need to be taken for what they are, a ball park figure.