Application of Isol8 Rb provides rubidium, taken up in a similar fashion to potassium, and potentially incorporated into biopigments appearing deep-red to purple, the degree to which this occurs being at least partly related to the predominant accessible form of dissolved inorganic nitrogen. Anecdotal accounts of shifts in coloration of corallimorpharians with consistent Rb supplementation may be a result of this process.

Rb must not be overdosed. A reliable ICP analysis (performed by a service provider who has the ability to accurately determine [Rb+]) must be performed prior to commencement of Rb supplementation, to ensure that dosing is consistent with existing system [Rb+]. Thereafter, ICP analysis performed on at least a monthly frequency will provide rate of system Rb uptake, enabling modification of Rb dosing as necessary.

Note that the use of zeolite intended to curtail ammonium content in recirculating marine ecosystems will also remove potassium and rubidium.

Recommended is diluting an appropriate volume of this solution into a larger volume of purified water (with a purity of at least 98%), and applying this diluted solution to the system with an automated dosing system. Dosing frequency is directly proportional to stability of ionic concentrations and, resultantly, continuous cohort biomass growth. A 1 - 10 s drip interval provides adequate ionic stability, and is recommended.

If no automated dosing system is available, then apply solution manually each day. Dosing frequency is directly proportional to stability of ionic concentrations and, resultantly, continuous cohort biomass growth. Dosage volume per 24 h is divided by the dosing frequency*.

It is not recommended that this formulation be dosed fewer than four times weekly.

Reference Standards: 1 mL Isol8 Rb diluted in 26.4 gal. (100 L) water yields 50 μg/L increase of [Rb].

To calculate required solution volume for known parameter differential:

1. Multiply net water volume (L) by actual [Rb] (ppm).

2. Multiply net water volume (L) by desired [Rb] (ppm).

3. Subtract product of Step 1 from product of Step 2.

4. Divide difference of Step 3 by 0.50. Answer is drops sol’n required to achieve desired [Rb] in situ.

Recommended: Do not increase parameter concentration by more than 5% per 24 h period in systems with existing cohorts. Aside from emergencies (e.g. excessive nutrient content in an active system, greatly depressed or excessive salinity, etc.), gradual changes in water composition are generally tolerated better by aquatic organisms than are rapid changes.

*Example: If dosage volume per 24 h = 1 mL and dosing frequency = 4, then dose 0.25 mL per event.