Help with my parameters

[oldss72]

Hello,

I have been keeping a Salt water tank for ~2 years now. I started with a 10 gallon fish only, then 20 gallon w/o sump, 20 gallon with 10 gallon sump, 60 gallon with 20 gallon sump and now 60 gallon with 55 gallon sump.

I set up my 55 gallon sump in my basement approx. 2 months ago because I was tired of spilling water during water changes in my living room, wanted to increase my water volume, and decrease the clutter under the stand.

Since setting up the 55 gallon sump, my corals with the exception of my mushrooms and leathers have been struggling. I have had ecoxotic LED lights over my 60 gallon since I set it up ~1 year ago. everything did very well then.

Approximately 8 months ago, I had an Ich problem - and lost all my fish with the exception of my copper banded. After re-introducing my copper banded and re-stocking my tank, I had nitrate issues which I thought was from the sudden increase of bioload. (copper banded, maroon clown pair, pajama cardinals - 2, blue chromis - down to 2 due to one going carpet surfing). The tank stabilized with the help of vodka dosing, and my nitrates tested at 4-8 for quite a while.

With other things going on, my water changes lagged, and My feedings increased. This caused my nitrates to increase again, and was up to about 50 when I decided to move the sump to the basement. Since then, I have been struggling to keep my nitrates low and have been doing large water changes. Nitrates have been around 8 for ~2-3 weeks now. I understand this is not too high, but my zoas and my polyps have looked bad and my LPS has declined.

My current water parameters are:
Mg - 1370 - (this was ~1120 2 weeks ago due to my water changes - tested new salt and found that my fresh oceanic batches were ~1100) (salifert)
Ca - 460 (salifert)
Alk - 8.0 (salifert)
Phosphate - 0.00-0.02 (hanna checker) - GFO reactor runs 8 hrs per day.
Nitrate - between 8-12 (red sea)
Salinity - 1.0255 (refractometer)
Water temp - 78-79F

I am dosing vodka 8ml per day - but it does not seem to have much effect. My skimmer works well (Reef octopus NW 110) - but I am beginning to think it is too small? FYI probably ~100 gallons total actual water volume with plumbing.

I also dose Alk (8ml per day - I think I have the sweet spot because it NEVER deviates from 8) and Mg (have been doing this to raise levels). My calcium never tests lower than ~450, so I have not dosed calcium in quite a while.

I clean my sump religiously when changing water. All the surfaces get wiped down of algae, there is a powerhead in the sump that keeps detritus from acclumulating. There is macro algae in the sump that is growing well.

One chamber in the sump is a 4" DSB. In this chamber I have some Button polyps which also look poor (thought lights may be the issue - under T5 lights, they look the same). The pipes are cleaned bi-weekly and never really show much accumulation. The return pump and skimmer are cleaned weekly. I change filter socks every other day. I am somewhat at a loss here - aside from increasing the skimmer size, I am not sure why my coral is struggling - especially when it was doing so well for quite a while. My leathers are huge and look great, as do my mushroooms and other softies.

I increased my cuc with lots more snails and crabs since I was getting some detritus in the display. I also changed around my flow pumps and 2x per week I blow all my rocks off - I hardly get anything coming off now, so I am happy with that and attribute that to helping my nitrate decent from 50.

Hoping another opinion will help - thank you for taking the time to read this and respond.

Joe

[shifty51008]

The thing that pops out at me is the gfo only running 8 hours a day, the rest of the 16 hours the water is not moving in the reactor so when it does start up that water could be whats causing the problem. But then again i dont know if 16 hours is long enough for it to go bad.

[bertoni]

I would avoid letting the GFO sit for 16 hours without circulation. I agree that a lot of anaerobic decay might be happening. I'm not sure that's the problem, though.

I would start by getting second opinions on the test kits and SG device. I'd worry mostly about the alkalinity, nitrate, and SG first, and maybe work from there. Soft corals should be fine with low alkalinity levels, though. The LPS might be more of an issue there, and it might react poorly to high phosphate, as well.

I don't know enough about the various protein skimmers to know whether the one you have is going to be okay. There's a general lack of knowledge about skimmer performance, in general.

[oldss72]

Thanks for the replys - I will change my GFO to run constantly and see if that makes a difference. It needs to be changed anyway as well.

On the alk - is 8.0 too low? I always thought 7-12 was preferred. I can easily raise my dosing (BM dosing pump) as required. What target would you prefer?

I will take a water sample to a LFS and have them double check my test parameters later this week. My alk. test kit is nearly spent, so I will be getting a new one soon, and may invest in a new calcium test kit as well for good measure. LFS started carrying red sea, and I really like their nitrate kit - I am going to start purchasing these in the future I think. I will also purchase some calibration fluid for my refractometer.

For the skimmer - It seems the general suggestion is that 2x the water volume is the suggestion - would others agree? This particular reef octopus model is rated to 100 gallons if I am remembering right. Initially I thought this would not be an issue since my actual tank size is smaller and therefore the amount of material I am asking it to pull out is low - but then I realized total % of water skimmed per day would be lower - which is why I am thinking this may be a concern.


Anything else I should look for?

[shifty51008]

Alk at 8 is fine as long as it is stable, corals dont like it all over the place but you having a dosing pump it sounds like it is fine.

As for skimmers i always go by the biggest one you can afford and also have room for it.

[bertoni]

I agree that alkalinity is fine at 8 dKH.

Manufacturer's ratings for skimmers need to be treated cautiously. They can be very optimistic. I'd wait for the second opinions on the test kits before investing any money, though.