Nitrate & GHA Battles

[Pmj]

Here's the story of my current nitrate and GHA problems. Tank is two years old and I have always had nitrate levels 15+, but more generally 30ish. Past six months or slightly more I've been dealing with pretty nasty GHA. It gets really bad and grows over/in/around corals and has killed more than a few. Here is the spec breakdown:

Tank specs:
34 gallon Solana
No Sump as it's an AIO setup with back chambers
Tunze 9002 skimmer
Koralia Nano & Jebao RW-4 powerheads
Temp: 78
SG: 1.025
Calc: 420
Alk: 9
Phosphate: undetectable API
Nitrate: usually 30ish, 40+ last check (also own Red Sea kit, but at these levels API is much easier)

Livestock:
2x Osc Clowns
2x Chromis
Gobi/pistol shrimp combo
10+ snails & crabs each
RBTA
Urchin (new addition to help eat GHA hopefully)

I understand the basics everyone always says to do"¦ feed less, lower light schedule, more water changes. I've tried changing the flow around a lot, but generally I always end up with how it is now as that is how corals are happiest. I've tried not running any filter on the back chambers, but if I don't the gunk just ends up accumulating on the back of the back chambers, which are hard to clean. I've being dosing vinegar for over 3 months now and I've never seen it really do much. I worked my way up to 25 ml a day and nothing ever looked better (in fact I feel it started to look worse and was getting the white film on the glass), and nitrates never dropped below 15. I have pretty much given up hope on carbon dosing, it could be my skimmer isn't good enough to work well with carbon dosing, but I still dose 10 ml a day to hopefully keep whatever bacteria I built up still alive.

There's two things I really think contribute to this all. For one, imo, AIO tanks suck. It seems like having near zero nutrients in an AIO is not realistic most of the time. I'm really just sick of this AIO and want to get a bigger tank where I can have a sump, refuge, reactors, etc. I'm trying to look for a new house so the plan has always been to wait till then for an upgrade though. Problem number 2 is my rocks aren't very good. They aren't very porous (which I think is probably the main problem), they are too big, and there are too many in the tank. Algae grows everywhere, but always in certain spots which I'm sure have low flow. The rocks are built up and resting on top of each other and against the false wall. If I could do it again (and after having seen minimalist scapes here on RC), I wouldn't have them stacked this way and would have room behind the rocks for flow. Corals have grown over everything though so throwing them out would be problematic.

My question is what should my next steps be? I've been debating these things:

I've thought of buying a small LED like the JBJ nano glo and try to grow chaeto in the back chambers. I've since read that chaeto is more of a preventive help than a fix for high nutrients. I'm guessing with a small crappy LED it will not work as well as it would in a bigger refuge with a bigger light. How much would doing chaeto in a back chamber realistically help?

I've thought of buying a GFO reactor and hopefully sucking phosphates out enough will kill the GHA, but this obviously won't help my nitrates. Can GHA grow with just high nitrates or will doing this kill it?

I don't know if my rock problem is easily solved. A while ago I bought some rock from BRS that looks great and is much more porous, but there is no space for it. I don't think there is any way to re-arrange my current setup. I suppose I could try to take the old rocks out and break them apart to save the corals, while putting the new, better rocks in. I could see this method being not good for the inhabitants and don't want to cause a crash accidentally. I also thought of breaking the newer rocks and putting it in the back chambers, but it doesn't seem like many people do that.

Thanks for reading and I appreciate any input!

 

[Sk8r]

GFO for the phosphate, perhaps carbon (vinegar) dosing for the nitrates, coupled with an aggressive set of water changes.

 

[Pmj]

GFO for the phosphate, perhaps carbon (vinegar) dosing for the nitrates, coupled with an aggressive set of water changes.

I have been leaning towards a reactor. Do you know if GHA can still live with low phosphate but high nitrate, or do both need to be very low?

 

[Sk8r]

Phosphate reduction will wipe out the hair algae. Nitrate reduction will help corals and fish.

 

[Reef Frog]

I believe most pest algae plagues are driven primarily by high phosphate levels, but high nitrates certainly play a role.

Excessive detritus build up is algae fuel in inventory. Export it regularly. Detritus is where tomorrow's nutrients will be coming from. I'm not sure about a Solanis, but not all AIOs accumulate detrius in the rear chambers. My RSM 250 accumulates virtually nothing back there. I'd run the filter pad. Having an AIO isn't causing your problem and gunk can easily accumulate in a traditional sump. Macro algae refufiums often are inadequate for heavy duty nutrient export unless they're quite large, well designed and maintained.

Dense non porous rock is known to be inhospitable to the anerobic species of bacteria that process nitrates into nitrogen gas that then leaves the aquarium. This happens mostly deep inside the rock. I think you're on to something here. But still, it can be controlled.

Try skimming wet to improve export of the bacteria that your carbon dosing should be producing. Remove detritus. Siphon it out of the DT. Run a filter pad or sock. I bet GFO in a reactor will help a great deal. Do more, perhaps bigger water changes. Hydrogen peroxide or Algaefix Marine are worth other options to kill GHA you have now while your nutrient control plan takes effect. It takes a while. Good luck.

 

[CStrickland]

Have you seen the newer fake rocks?
There's one type called marine pure, and another with a weird name like siporax. They are meant to be fairly small bricks or chunks that have vast internal surface area for denitrifying bacteria. Some people have had really good luck with them, and you might have room in your back area. There are a few threads about those options in the chemistry forum.

Also, keeping the tank clean really helps with nitrates. If the back chamber is hard to access and collecting detritus that can be an issue, same with rubbley substrate like crushed coral. I find vacuuming my sand to help a lot, but you need to start slow and only if you have less than a few inches.

I never had nitrate issues until I lost my temper a few weeks ago and tore apart my aquascape. My nitrates shot up and the algae outbreak was right behind it. It's hard to get down once it's bad, my sympathy.

Also, is your skimmer set to skim wet enough? You should be needing to empty a tea colored production a couple times a week if you're carbon dosing.

Edit: HAHAHA reef frog was typing a lot of the same things as me, just faster. lol. I feel so smart!

 

[Pmj]

I believe most pest algae plagues are driven primarily by high phosphate levels, but high nitrates certainly play a role.

Excessive detritus build up is algae fuel in inventory. Export it regularly. Detritus is where tomorrow's nutrients will be coming from. I'm not sure about a Solanis, but not all AIOs accumulate detrius in the rear chambers. My RSM 250 accumulates virtually nothing back there. I'd run the filter pad. Having an AIO isn't causing your problem and gunk can easily accumulate in a traditional sump. Macro algae refufiums often are inadequate for heavy duty nutrient export unless they're quite large, well designed and maintained.

Dense non porous rock is known to be inhospitable to the anerobic species of bacteria that process nitrates into nitrogen gas that then leaves the aquarium. This happens mostly deep inside the rock. I think you're on to something here. But still, it can be controlled.

Try skimming wet to improve export of the bacteria your carbon dosing should be producing. Remove detritus. Siphon it out of the DT. Run a filter pad or sock. I bet GFO in a reactor will help a great deal. Do more water changed. Hydrogen peroxide or Algaefix Marine are worth other options to kill what you have now while your nutrient control plan takes effect. Good luck.

I didn't mean to solely blame the fact that it's an AIO. I'm just annoyed with it b/c I don't have many options as far as better hardware (skimmers, reactors), space for things like beneficial algae, or much room to do anything at all. At least a normal sump would be easier to clean.

Next steps I'm going to get a reactor and run the skimmer wetter. I don't know where I'm going to put the reactor, but at this point I would even leave it standing in the back chambers. I've thought of putting it in the stand but will probably need longer hoses and some type of clip to keep the return hose in the tank.

 

[edinphilly]

Very good advice from the last two posts. I would add before sinking more money into "maybe" fixes if it were me I would have someone double check the nitrate and phosphate readings to confirm what you're getting with a different kit. That eliminates possible bad test kit. Also, have you tested your source water? Meaning is your water 0 TDS with no nitrate or phosphate before you mix the salt in?

 

[Pmj]

Have you seen the newer fake rocks?
There's one type called marine pure, and another with a weird name like siporax. They are meant to be fairly small bricks or chunks that have vast internal surface area for denitrifying bacteria. Some people have had really good luck with them, and you might have room in your back area. There are a few threads about those options in the chemistry forum.

Also, keeping the tank clean really helps with nitrates. If the back chamber is hard to access and collecting detritus that can be an issue, same with rubbley substrate like crushed coral. I find vacuuming my sand to help a lot, but you need to start slow and only if you have less than a few inches.

I never had nitrate issues until I lost my temper a few weeks ago and tore apart my aquascape. My nitrates shot up and the algae outbreak was right behind it. It's hard to get down once it's bad, my sympathy.

Also, is your skimmer set to skim wet enough? You should be needing to empty a tea colored production a couple times a week if you're carbon dosing.

Edit: HAHAHA reef frog was typing a lot of the same things as me, just faster. lol. I feel so smart!

Thanks, going to look into the fake rocks possibly in the back chambers. There's really nothing in my middle chamber now.

 

[Pmj]

Very good advice from the last two posts. I would add before sinking more money into "maybe" fixes if it were me I would have someone double check the nitrate and phosphate readings to confirm what you're getting with a different kit. That eliminates possible bad test kit. Also, have you tested your source water? Meaning is your water 0 TDS with no nitrate or phosphate before you mix the salt in?

I have a BRS RODI and changed all the filters a month ago even though I was still getting 0 TDS.

You're right I can take the water to a LFS and have them check too.

 

[edinphilly]

I have a BRS RODI and changed all the filters a month ago even though I was still getting 0 TDS.



You're right I can take the water to a LFS and have them check too.

Regardless of the outcome of that if you're having the algae issues I would say it's safe to say you have some nitrate/phosphate issues. I did for a while from known sources (live rock that had started in a tank with tap water and had absorbed phosphates, and nuking a bunch of waving hand coral to get rid of it all led to a spike with the die off). That's when I started GFO and it was worth it, so I'm not suggesting that's a waste of money just that it would be worth double checking the tests. I almost screwed up my tank because of a bad magnesium test kit. Luckily a good LFS figured it out early for me.