Help: SPS bleaching and STN

[gregzz4]

Originally Posted by Myka

Another thought is that I don't think those MP10s are really strong enough on that size tank for SPS. I think it would have been better to buy two MP40s

You think 4 x MP10s isn't enough for a 70G tank ?

I'm running 2 x 10s in my 75G and can't run them @ 100% without either blowing flesh off corals/polyps stop growing on one side, or causing them to grow sideways away from the props

[lastlight]

i've got 2 x mp10s in my 93 cube and they're at 70%. All my SPS are happy.

[Myka]

Originally Posted by gregzz4

You think 4 x MP10s isn't enough for a 70G tank ?

I'm running 2 x 10s in my 75G and can't run them @ 100% without either blowing flesh off corals/polyps stop growing on one side, or causing them to grow sideways away from the props

I don`t think you`re setting your powerheads up very well then. Certainly you can`t place powerheads so they shoot directly at corals. The MP10s are only 1500 gph full blast which isn`t enough to push across a 48 inch tank. If the MP10s were situated on the back glass pushing towards the front more velocity may be able to be made. SPS though need a lot of water movement throughout the tank and appreciate velocity.

My 90-gallon which is very similar dimensions to a 75-gallon has two Tunze 6105 (3400 gph) and a 6055 (1450 gph) and I can run all of them full blast with the narrow outputs on them and as long as I have the powerheads situated well my corals will keep their flesh on. My tank has about 92x turnover where the OP`s tank has about 80x turnover. Even though these numbers are quite similar, the larger pumps in my tank create higher velocity.

The Tunzes`new wide flow output option is really cool because you can get the same amount of flow with less velocity. LPS do not appreciate velocity. In a mixed reef like the OP`s, creating flow that makes all the corals happy is challenging.

Chizer, I would try moving those MP10s around to create more velocity near the SPS. If you set them up on the back glass pointing towards the front glass you should be able to achieve this. The VorTechs can be a bit awkward though since you can`t control their direction.

It could very well be the tap water though.

I wish that was an option. I have a large coast to coast external overflow on that entire back wall so it limits me to placing the MP10's at the bottom half of the tank. I had thought about building my rock up with PVC and laying them on egg crate, then it would give me that velocity.

What do you think? Will this look tacky? My SPS will then be about 6" from the surface.

I am going to buy a RODI unit from BRS. Just looking at the cost of RO in my city, it's going to be $40 just to do a 40 gallon water change. That's not including the ATO water of 15 gallons a week.

Also going to try some BRS GFO in a media bag, in my filter sock. But I'll put it on the output of my protein skimmer.

I really want to get a way from carbon dosing entirely. It's scaring me off.

I am thinking it was a combination of ALK ( initially at 7 and then I slowly raised it to 8), and bad water quality. Lesson learnt, listen to people's advice as they have been there, done that.

[daniella3d]

If you are paying for your water, then you might want to consider a RO unit that is low on water usage like this one, which will waste no water, so cost much less at the end:

http://www.costco.ca/Premier-Zro-Pur...100016456.html

If you are using tap water I would start with using RO. This is probably your problem.

Originally Posted by ChizerBunoi

I am going to buy a RODI unit from BRS. Just looking at the cost of RO in my city, it's going to be $40 just to do a 40 gallon water change. That's not including the ATO water of 15 gallons a week.

Also going to try some BRS GFO in a media bag, in my filter sock. But I'll put it on the output of my protein skimmer.

I really want to get a way from carbon dosing entirely. It's scaring me off.

I am thinking it was a combination of ALK ( initially at 7 and then I slowly raised it to 8), and bad water quality. Lesson learnt, listen to people's advice as they have been there, done that.

Thanks for the link Daniella. That was the main reason why I didn't purchase a RODI in the first place. It just wastes so much water. I'll check out that unit you posted.

[cblair]

If you are running zeovit to lower nutrients then definitely get your dkh down to 7-7.5 and keep it stable there. I started zeovit in my tank 2 months ago and I can say that higher dkh than that you will start noticing burnt tips on some acros which will lead to stn. That's just my experience so I would try to work on lowering your alkalinity.

[Myka]

Originally Posted by ChizerBunoi

What do you think? Will this look tacky? My SPS will then be about 6" from the surface.

Yeah, it probably will. If you don't have something laying around you could use (like a cheap Koralia that you can put the back magnet into the overflow) then just try the RO. Your SPS are fairly small still, so it may not be a flow issue. As they grow you're probably going to get some trouble. If you see a good deal on an MP40 I would probably pick it up if I were you and replace two of the MP10s with one MP40.

I am going to buy a RODI unit from BRS. Just looking at the cost of RO in my city, it's going to be $40 just to do a 40 gallon water change. That's not including the ATO water of 15 gallons a week.

Ouch. Yeah, that's a good plan. Talk to someone in your area that knows RO/DI systems really well to figure out which filters types work best. Here in Saskatoon we have chloramines to worry about, in Alberta I know many areas have really high iron content. I have no idea how that may or may not affect RO/DI systems. If you don't know a fish RO/DI expert, ask a drinking water company and just tell them you're looking at options for drinking water. They will tell you what you need for stages, and then buy it at BRS for 1/4 the price.

I am thinking it was a combination of ALK ( initially at 7 and then I slowly raised it to 8), and bad water quality. Lesson learnt, listen to people's advice as they have been there, done that.

I don't think it is the alkalinity. Tanks that run biopellets are prone to RTN if the alkalinity is above 8 dKH. Zeovit tanks are also supposed to run around 7 dKH. Natural seawater averages around 7 dKH. My reefs both run 7-8 dKH.

[Myka]

I was just looking at your pictures again...

I see some algae growth on the back glass and the pumps, are those the only places in the tank that have algae? How long since you cleaned it off last? I notice also that you have few fish and run BB. You do feed the corals some, but what I'm getting at with these new questions is maybe the corals are starving. The nutrient level is really low. Do you feed the Reef Roids at night when the SPS have their feeding polyps out? Are you getting a good feeding response when you feed the Reef Roids?

[gregzz4]

Besides Myka's good thoughts, I'll add my similar issues from the last few months (or maybe a bit longer)

It sounds like you may be having similar issues to mine and your tank is 'too' clean. I found out our corals need food, or they will bleach

My corals were bleaching pretty badly
I had zero nitrates and phosphates, so some fellow reefers helped me out
Our thoughts are that I wasn't feeding my fish enough, and not feeding my corals, so the corals expelled their zooxanthellae. Once the zoox are gone, there's nothing to protect the corals from my 8x54w light, so bleach away

I turned off half my lights, started feeding the fish double-time, and also started using coral frenzy, phyto plan and coral vitalizer
A couple of weeks and the corals were coming back
Now all are looking much better, and I'm getting the new algae under control
I've also started playing with my lights to get a happy medium between the corals and our viewing times

I see your lights are a total of 15 hours for 3 pairs
I knocked mine down from 27 hours for 4 pairs, to 19 hours for 2 pairs for a couple months. This worked very well for me and I don't think your lights are on too much
I'm currently running a total of (I think) 20 hours total with 4 pairs and all is looking good. It's been many months since I started making changes, so don't expect a quick fix

I also see you wash your socks daily. Do they plug up this fast, or are you just cleaning them 'cause ? I wash mine once a week. Maybe you're removing more nutrients here than you need to

And you run your skimmer very wet. Maybe it's of no consequence, but I run mine dry and only remove a few hundred ml/week, and the nog is very dark

Hope this helps some