Hi,

My Caulerpas (featherlike types) don't feel so well after I tried dosing just a little KH2PO4. I tried it two times, and it seems that otherwise healthy leaves just break loose and floats away. Some red algae gets some kind of green necrosis in the middle and melt from there. Weird.

Are you dosing KNO3 as well and traces?

KH? Ca?

Regards,
Tom Barr

Yes, both KNO3 (less then 1/16th of tsp), traces 1 ml (like TMG), KH and CaCl2 2-3 ml each. This pulse about 2-3 times a week. The aquarium is about 35 L.

I've not dosed PO4 for a week now with no ill effects on any of the plants. I've increased KNO3 a little. My caulerpa prolifera gets transparent tips if I don't keep up. I may actually be dosing less traces than you even though my tank is bigger, at 75g, with a fairly large plant mass. What I'm using is the Kent macro trace mix which is like water compared to TMG.

At the moment, unless I can nail down a definite PO4 defficiency, I'm not going to bother with it for now. PO4 is an enigma for me. It's needed, but not too much not too little.

I'd be careful dosing it and only when you rule out other issues or have intense peroids of growth, would I suggets dosing it.

You do not need much to remove the PO4 issue either.
Diatoms are the main issues with addign too much. I never found it did anything bad to Caulerpa though.

Regards,
Tom Barr

Mmm, but what else can I blame Caulerpas bad health on then? It's just so strange: when I dont add anything (no KNO3, PO4 and so on) Caulerpa slowly grows - pretty pale in color, but growing. When I add all of the above things, Caulerpa gets deep green, really nice looking, but starts loosing its leaves at the root. Really weird. Wasn't it the kind of thing you Tom observed here:


From: Reef Central Online Community - Adding more nutrients to a nutrient lacking system?

Sounds like maybe something else is going on in your tank.
Nutrietn alone are not accounting for it.

Some new growth white tips can be normal, but it seems more like lack of Ca or something, rather than PO4 etc.

Regards,
Tom Barr

Allright, I'll try to change some water, maybe it helps. I don't really know if it's Ca, 'cause Halimeda still shooting new leaves now and then.

Thanks Reiverix, for input. Have you observed some deficiancies for KNO3 and therefore increased? What's your fullpulse now?

Any special reason for using Kent's trace mix if it's so diluted? Maybe I overdose with TMG then..

Or maybe it's the lack of CO2 in my case? And it appeared after I adressed the macronutrients? Maybe I should install more powerheads - as it is now i have about 20 times the entire volyme turnover per hour - could it be inadequate for supplying all the CO2 to the algaes? I know it could be a long shot, but who knows..

I can't say for certain that I observed a KNO3 deficiency. It may be that N and traces go hand in hand. So far it's working and I'm kind of relieved to get PO4 out of the picture for now.

The only reason I went for the Kent trace mix is because I'm the newbie here I would rather dose light and observe after 24 hours. Increase or decrease as needed.

KNO3 is at 2ppm every two days. I'm slowly reaching a target of around 5pmm with a max of 10ppm. I've not tested for more than a few days so I'll have to do that tonight and see how much my uptake is changing. The caulerpa can get quite weedy.